One of my rules for covering the auto industry is to never judge a new car based on the manufacturer’s preview.

It is all too easy at these events to get swept up in an atmosphere of artificial excitement. You have been flown to some distant resort in California or Arizona in the middle of winter for a test drive. You are seeing a car for the first time, weeks before the general public. And you are surrounded by engineers, executives, and public relations operatives whose jobs depend on generating excitement for the vehicle at hand.

What car ever looks bad under these circumstances?

Last spring, I violated my own rule after driving the new Toyota Prius gas electric hybrid at a long-lead event in Napa Valley. I loved the car. For one thing, I was preconditioned to treat Toyota’s technical achievements with shock and awe. After I succeeded in hyper-miling the Prius to in excess of 70 miles per gallon, I was hooked. Talk of a $23,000 base price for the technological marvel was a bonus.

Well, six months later and I’m driving a Prius on my normal weekend test route. In the cold light of day, all those techno touches seem more curious than clever. The extreme aero shape of the body has left the instrument panel several feet away and made me feel as if I am driving from the middle of the car. The transmission shifter on the dash requires a re-education and some of the controls are bizarrely located (the seat heater switch is located down by my knee and completely out of sight).

That $23,000 starting price, meanwhile, has become a mirage. I have borrowed a car from one of the high trim level series, and the addition of the Advanced Technology Package (dynamic cruise control, pre-collision system, intelligent parking assist) has jacked the price up to $32,771.

After logging more than 200 miles on my normal test route, I was getting a smidgen over 50 miles per gallon – good but nowhere near my 70-plus mpg at the preview.

I have discovered I don’t really drive the Prius – I guide it. The combination of the awkward seating position, weird controls, pokey acceleration (zero to 60 in 9.8 seconds), and elongated aero shape makes me feel like I am traveling in a space capsule rather than riding in a car.

None of this is a knock on Toyota. It has created the world’s most popular – make that the world’s ONLY popular – gas electric hybrid, delivered on its fuel economy promise, and put it on sale at a reasonable price.

But it is a reminder to potential buyers that Prius is something special and doesn’t look, touch, or feel like a traditional gas-powered car.

And it is a reminder to me to never, never judge a car based on a manufacturer’s preview.

The supercar has been a struggle to sell, which means potential bargains for interested buyers.

Among the more exotic niches of the car business is the marketing of supercars.

The cars, which carry price tags in the mid-six figures, require a tricky marketing balance. If they become too scarce, speculators move in, driving up prices and making the cars unavailable to enthusiasts. But if too many examples show up on the market, they lose the appeal of scarcity and potential buyers move on to the next big thing.

Consider the case of Mercedes’s SLR McLaren. Based on its spec sheet, the car should have been a home run when it appeared in 2004. It had a supercharged V-8 engine that put out 617 horsepower and got the car from zero to 60 mph in 3.6 seconds; its top speed was 207 miles per hour. It sported an advanced carbon fiber body and retro scissor-style doors. The SLR also had a history behind it. It was said to have been inspired by the Mercedes 300 SLR of 1955.

But the market for supercars was weakening when the SLR came out, and the car received some middling reviews. There were complaints about its styling and its function — whether it was really a sports car or a grand tourer in disguise. Mercedes had planned to sell 500 SLRs a year at $495,000 each, but after 2005, it wasn’t able to achieve that goal. It ended production of the car in 2009 — two years ahead of schedule.

Today, the SLR is unloved and unwanted. According to one dealer, there are currently 26 unsold cars at the port in Los Angeles. Based on last year’s selling rate, that would be a three-month supply. A Mercedes spokesperson says that number is too high — she says “only a handful of SLRs are there” (though there may be more in East Coast ports).

If you want to buy an SLR for Christmas, now is the time for a bargain. Mercedes says that if you group all the wholesale and retail dealer allowances together, you could knock the price down by $175,000. A dealer says the number is actually higher: $250,000 off the sticker.

But if you think the SLR has become damaged goods, never fear: a new Mercedes supercar is on the way. The 2011 SLS AMG, introduced at the Frankfurt Motor Show in September, gets a 571 horsepower V-8 that will fling the car to 62 mph in 3.8 seconds, with a top speed of 197 miles per hour. In addition, it has genuine butterfly doors. The estimated price is $225,000 or less than half the price of the SLR.

Caveat emptor.

Are better times coming? Ford seems to think so, based on the design and features of the new Lincoln MKT.

When you want to take the psychic temperature of the Ford Motor Co., all you have to do is look at the latest offerings from Lincoln.

When times are tough, the company makes little effort to distinguish luxury-pretender Lincoln from its homelier Ford origins. A new grille here, redesigned tail lamps there, and you have summarized the major differences between, say, the Ford Edge and Lincoln MKX.

But when better times are coming, Ford digs deeper into its product development budget to more fully differentiate Lincoln and add more luxury features.

Cue the 2010 MKT. While it’s based on the utilitarian Ford Flex people-mover, the MKT looks nothing like it, with a new body panels and unique design flourishes like the upswept kink in the rear fenders. For proof, park the MKT in your driveway and you won’t find anybody whispering “poor relation.” At 17 ¼ feet long and weighing nearly 5,000 pounds, MKT is an imposing piece of automotive iron — half a foot longer and 350 pounds heavier than the Flex.

Evaluating design is a subjective matter. I like the MKT’s split waterfall grille, but found the tailgate-wide rear insignia/taillight treatment a bit extravagant.

Inside, the interior is a masterful combination of luxury and utility, marred only by retro-styled instruments that are hard to read. And watch out for the Collision Warning with Brake Support system. Pull up too close to the car in front of you and a dozen LED lights start flashing in the windshield while the radio signal is damped and alarms blare. You’d think you were at Three Mile Island during a meltdown.

Reviewers have praised the performance of the MKT — and with good reason. The optional EcoBoost V-6 engine with twin turbochargers lights up quickly with the push of a button and gets the car underway so smoothly you would swear you are driving a V-8. Another plus: There is no turbo lag and no turbo whine. An additional EcoBoost payoff comes from fuel economy: The MKT with all-wheel-drive gets 16 mpg city/22 mpg highway, about the same as a Flex AWD with a standard V-6 that produces only 265 hp. I confirmed the highway figure during a 100-mile run.

All that technology, performance, and carrying capacity for seven carries a significant price tag. The MKT’s base price is $49,995 (including delivery), making it the second most expensive vehicle in the Lincoln lineup after the Navigator. My optioned-up test vehicle was listed at a stiff $57,180.

At least you likely won’t see yourself coming and going. Lincoln is still a low-volume brand and Edmund’s reports that MKT sales are off to a slow start.

Yet it is good to see Lincoln acting like a real luxury car contender, and better still to know that Ford sees bluer skies ahead.

For as long as I have been writing about cars, Acura, the move-up division of Honda, has been struggling to create an identity for itself.

Part of the problem is its positioning. Unlike Lexus and Infiniti, Acura was never conceived as a full-bore attack on the German luxury carmakers, but rather a step up for Honda buyers. So while Acura markets cars in small, medium, and large sizes, just like the Germans, they are several notches lower in price and prestige.

Another part of the problem is perceived exclusivity. Two-thirds of Acura’s current passenger car lineup is based on the Honda Accord sold in Europe, a heritage that isn’t going to appeal to status seekers. Over the years, Acura’s styling has been appropriately conservative without being distinctive. And its nomenclature is forgettable, with the model range designations going mysteriously from TSX to TL to RL.

So while Acura is three years older than Lexus or Infiniti, it hasn’t been able to use those extra years to establish a higher profile. Even difficult economic conditions haven’t helped, despite Acura’s generally lower price points and superior gas mileage. Its sales have fallen 34% this year, more than its luxury competitors.

A car that could raise Acura’s recognition factor is the TL, the mid-size in the lineup. Powered by a 305-horsepower V-6 and available with a six-speed manual transmission, it has been praised by enthusiasts for its smooth shifting and zesty performance.

I was less impressed. When navigating through a six-speed gearbox, it is helpful to have an indicator of the instrument panel to tell you what gear you are in; Audis do but this Acura did not. The TL also seemed to reward higher-rev shift points than I am accustomed to using. Down in the lower revs, I found myself downshifting frequently on hills despite the reputedly torquey characteristics of the engine

What I did like was the TL’s design: aggressive but not so much as to scare small children. The paint job, in a deep radiant black, sets a standard for this class of car. The interior was as handsome as Honda products ever get, and the instruments were characteristically clear in function and easy to use.

Honda likes to position the TL as a rival for the BMW five-series. With an as-tested price of $44,195, that would make the Acura a bargain. I’d rather think of it as a range-topping Accord with a special appearance package. And I would very much like to test one with an automatic transmission that does the shifting for you to fully appreciate this impressive machine.

In my experience, all proper German cars come in two colors: silver and black. There is a reason for this, as there is in all things German. These colors denote a seriousness of purpose, obliviousness to fashion, and a sticker price that takes your breath away.

But when I asked Mercedes to review an example of its new E-class line, the car I received was not silver or black but red — “Mars Red” in official Mercedes-ese.

I was confused. Was Mercedes trying to send me a message that times are changing at the world’s oldest automaker? Or had all the silver and black cars been snapped up by my competitors at Motor Trend, Edmunds, and Jalopnik?

Let’s review the evidence.

The E-class coupe replaces the two-door in the Mercedes lineup formerly known as the CLK and becomes part of the larger, more expensive E-class line. That’s one change.

Physically, the car harks back to its CLK roots but psychically, its aura has changed. The dimensions of the E-coupe platform are identical to the smaller, less-expensive C-class yet the car has the fittings, feel, and solidity of a larger E-class sedan. You could say the E-coupe merges C-class specifications with E-class ambiance. That’s another change.

My test car, which was equipped with a 5.5-liter, 382 hp V8, bristled with as much muscle as I wanted to handle, and the interior was top shelf. On the road, the coupe displayed the ride and dynamics of an E-class, combined with the handling and fuel economy of a C-class. In Mercedes tradition, comfort and predictability took precedence over razor-sharp reactions.

Fuel economy was impressive. Under the EPA driving cycle, the E-coupe is expected to deliver between 19 mpg and 27 mpg on the highway, and I consistently hit in the high end of the range.

That was good for the environment but not for my bank balance, since the premium grades of gasoline that Mercedes recommends run 10 cents to 20 cents more a gallon than regular.

The final piece of evidence showing that the E-coupe represents new thinking was the price. Mercedes prices its coupes aggressively but this was still a surprise. The base sticker price of the smallish E-coupe is $54,650 , only $1,650 less than the larger E-class sedan.

My car was equipped with the premium package (navi system, upgraded audio, rear view camera), Distronic Plus package (smart cruise control, parking guidance), appearance package (wheels, seats) and the wood/leather steering wheel package.

All together, that pushed up the total retail price to $67,125. That’s a handsome price for a handsome car in these economically distressed times.

By way of comparison, for the same money, you could move up two classes in size and pick up a used S-class sedan — a proper silver or black one.

If General Motors is able to convince the world that it can build cars that people actually want to buy, it has to start with the new models it launches over the next several months. Taxpayers, customers, and journalists all will be watching carefully.

In a sense, the attention is unfair. These are Rick Wagoner cars, planned and developed three years ago under the former CEO. Fritz Henderson cars won’t be coming along until 2012.

Still, GM has been arguing for some time that it builds world-class automobiles; all that’s missing now is its ability to convince convincing customers about the validity of that claim.

The 2010 Buick LaCrosse perfectly illustrates the problem. Stick a Lexus or an Acura label on it, and you would have a competitive car, one you would take on a second honeymoon to Napa Valley.

Let people know it is a Buick, however, and they expect to see it parked in front of Applebee’s for the early-bird special.

Badging aside, the LaCrosse ranks as my favorite GM sedan. Driving around the Detroit area, I was never disappointed.

What did I like about it?

First of all, the price. Even with 18-inch chrome wheels and other options totaling $1,850, the LaCrosse carried a sticker price of just $31,495. That’s a really good value for an entry-luxe mid-size sedan.

Second is the exterior design. With its high belt line, fast sloping rear end, and tasteful chrome accents, the LaCrosse is international in character and American in spirit. I even don’t hate the porthole simulations on the hood.

Third is the interior, bright and classy without being garish. You can argue about the unnecessary stitching, plastic wood, and overly busy instrument stack. But overall I felt comfortable and pampered, without any pandering.

Over the road, the Buick behaves like a large front-wheel sedan for aging baby boomers. Performance from the 3.0 liter V-6 is adequate — 60 mph arrives in eight seconds. For those who want more power, a 3.6 liter V-6 is available. The cabin is well insulated to screen out any unwanted noises. Fuel economy is an acceptable 17 mpg city/26 mpg highway.

For Buick to succeed and GM to prosper, the brand has to attract buyers who bring the average owner age down by a decade from the high 60s. Some better advertising and smarter marketing should do the trick.

With LaCrosse, Buick has the hardware; all it needs now is the image to go with it.

Poison for many manufacturers, the 2009 model year has been an elixir for Subaru. It is one of only two brands (the other is Kia) to show a sales increase this year. In an industry that is off 27.9% for the first eight months, Subaru is up 11.2% and is closing in on Mazda for 11th place in overall U.S. market sales.

Subaru manages all this with just three car lines and one truck (Mazda currently has a total of eight) and in this case focus pays off. The pre-production Legacy sedan I drove recently (Legacies are the top of the Subaru line) looked and felt like a much more expensive car. Base price is $19,995, but even at $24,995 (plus a $695 delivery charge) for my test car, I believe it is a remarkable value.

Subarus used to have a quirky streak, but the all-new mid-size Legacy looks muscular and mainstream without being boring. Inside I felt unusually well looked-after. The cabin was upscale without being fussy and the level of workmanship surprisingly high. All the touch points and instruments were sturdy and functional and unlikely to lose their appeal after years of use.

That’s an important consideration for Subarus. I have a friend who happily putts around in a Legacy wagon that dates from the first Clinton administration. It isn’t particularly stylish, but it is reliable, and he sees no need to replace it.

Like all Subarus, the Legacy comes with standard all-wheel drive and a new CVT transmission that boosts the EPA mileage rating to 23 mpg city/31 highway. That is so good that it beats the rating for the manual gearbox.

Oddly, Subaru provides paddle shifters for gear changes on the CVT, even though the transmission has infinite variability with no fixed gear ratios. I found myself downshifting on hills in order to maintain speed but I needn’t have bothered.

It is a little difficult for me to identify the factors behind Subaru’s success. It has been successfully upgrading its product line, but all manufacturers try to do that. Unlike Kia, Subaru has been building from a solid position to a stronger one, so there’s nothing dramatic there, either. Nor has there been any standout model or eye-catching ad campaign to create buzz.

So attribute Subaru’s success to the company’s unspectacular but highly competent management team, their U.S. headquarters in a Philadelphia suburb well away from the automotive mainstream — and a buying public that, in difficult economic times, knows where to find a good value.

Think of Subaru’s success in 2009 as a victory for common sense.

The minute I climbed into the driver’s seat, I knew: General Motors is getting its mojo back.

It may sound strange, but for a long time GM has felt lost in the product development wilderness. Some of its cars were simply duds. Others, even the ones deemed more successful, like the Chevy Malibu and Cadillac CTS, felt overly thought out and excessively mannered.

GM has been in the car business for 101 years. Why did it seem to have to relearn what it is doing, time and time again?

My Equinox experience was especially notable given my opposite reaction to a similar vehicle, the Cadillac SRX, a few weeks earlier. The SRX felt like it was developed by following the results of focus groups that weren’t coordinated with each other. The result was a mashup of features and functions that didn’t match up.

Not so in the Equinox. Everything is of a piece and seems to fit this midsize crossover. Its controls are all in the right place and function smartly the way they should, and none of the instruments or trim was fighting for my attention.

Likewise, the exterior design was well-resolved and identifiably Chevy, without slopping into the self-referential or overly mannered.

Unfortunately, some of the good feeling abated once I got underway. Although the Equinox came equipped with the optional 264-horsepower V6, it labored going up hills, refusing to shift down until the very last moment.

Would that be a deal-breaker? It depends on the terrain where I expected to drive.

The Equinox competes in a cutthroat segment against Honda’s CR-V and Toyota’s RAV-4. It is up to a foot longer than the competition and weighs several hundred pounds more but carries nine cubic feet less.

As the newest car in the segment, the Equinox is also the priciest. Loaded up with more than $5,000 worth of optional equipment, my test car carried a sticker price of $33,235.

It isn’t the best, and it isn’t cheap, but I consider Equinox competitive in this segment, and it has been a long time since I’ve been able to say that about a non-truck GM product.

The success of the Equinox bodes well for future Chevys due in the next year or so, like the Cruze, Spark, and Volt.

Getting its mojo back would be good for GM and good for the rest of the auto industry. GM should devoutly hope that Equinox is not just one of a kind.

Let’s get it out of the way right at the top: The new convertible version of Aston’s V-12 powered 2+2 grand tourer (with automatic transmission) carries a sticker price of $285,990.

That’s crazy, right, as we struggle to emerge from the worst economic downturn since the Great Depression?

But let’s consider this: The DBS Volante is the most drop-dead gorgeous, most satisfying car I can ever remember driving.

More refined and sophisticated in appearance than a typical Italian supercar, yet more expressive than a Porsche or a Jaguar, the Aston is stunning to look at. Every detail, from the four mesh inserts in the hood and the flared headlamp openings to the carbon fiber door handles is executed with an extra helping of panache that elevates it from the merely attractive to the alluring.

My test car glowed in a hue that Aston endearingly describes as Hardly Green that was both unique and eye-catching, and worked nicely with the brown leather surface coverings.

The view from behind the wheel is no less stunning. The winged Aston emblem dominates the steering wheel, the instruments are finely calibrated, and the Bang and Olufsen audio provides superb fidelity.

Fire up the six-liter engine by inserting the ignition device in its slot, and the Aston barks to life. Onlookers snap to attention. Select a gear by punching one of the traditional Aston dashboard buttons and you are off.

Power arrives smoothly and you can feel the six-speed transmission shifting smoothly up and down through the gears, proceeding so smartly that manual gear changes would be an insult to the software.

My agreement with Aston prohibited me from performance tests like 0-60 acceleration, so I can only report the company’s claim that 62 miles per hour can be reached in 4.3 seconds and top speed is 191 miles per hour.

As for flaws, I can identify but two: The carbon fiber chin spoiler is so close to the ground that it inhibits travel over rough surfaces, and the trunk is too tight to accept a bag of golf clubs.

But practicality isn’t the point here. Like a fine watch, the DBS Volante represents an ambitious expression of the mechanical arts.

For those who can afford to indulge such pleasures, and who can accommodate a Volante in their fleet of automobiles, it is an entirely worthy addition.

I would consider it a modern-day classic, for which paying the unreal sticker price is merely part of the pleasure of ownership.

Jaguar is at another turning point in its storied and eventful history. It is operating under a new owner, Tata Motors of India, while it launches models developed under its old owner, Ford.

The global economic downturn hasn’t been kind to Jaguar but it hasn’t impacted its product cycle either. Coming soon to dealers is the XF-R, a supercharged version of the midsize sedan, and an all-new XJ — the Jaguar flagship.

The model under review, the XK-R, has also been reworked for 2010. The spiritual, if not functional, successor to the historic XK-E, this two-plus-two features a new supercharged V-8 engine that puts out 510 horsepower and hustles the coupe to 60 miles per hour in a reported 4.6 seconds — should you have an opportunity to exercise it in that fashion.

The interior has been made over as well, with instruments and a silver rotary gear selector adapted from the XF. The gear selector has been criticized by some as too gimmicky, but I found it more ergonomically suitable than the dashboard mounted switches that the German luxury car makers have been experimenting with.

Historically, Jaguars have been among the most esthetically-pleasing (if not mechanically accomplished) cars on the road, and, for me, the XK-R is one of the Jag’s greatest hits. There isn’t a false note or awkward line on it, and the overall shape, with the long hood and suavely tapered rear, is enormously appealing.

The car drove the way it looks, smoothly and effortlessly. The level of intensity it required entirely depended on the demands made by the driver. All of its power and dynamic capability waited unobtrusively until it was requested.

The price for this élan is not insignificant. With 20” wheels and special paint, the total suggested retail price on my car came to $102,000. For those whose lives can accommodate what is basically a two-seat hatchback, and have the means at their disposal to afford it, the XK-R is a worthy investment.

Jags are still made in the U.K. and still source most of their parts from the British homeland. So those who turn up their noses at the idea of this fine old marque under Indian ownership have no substantive issues on which to base their bias.

Yet, as Tata, which bought Jaguar in 2008, enters Western markets for the first time, it is faced with a significant challenge. It has inherited a piece of automobile history that has been buffed to a high sheen by its previous owner. It remains to be seen what Tata make of the automotive heritage with which it has been entrusted.