The Audi A4 is a common car, that's actually very uncommon.

As the automaker's best-selling model, the compact sedan carries a heavy burden in showrooms. Over the years, changes made to its famously clean-cut and aerodynamic body have been subtle, in order to keep from frightening away its loyal customer base. With heavy hitters like the BMW 3-Series and Mercedes-Benz C-Class looming in the shadows, it’s easy to understand why.

In 2009, however, the sheep was thrown to the wolves. The A4's new clothing gets a radical injection of sex appeal. Formerly slab sides have been replaced with character lines and curves, and the front fascia festooned with no less than seven crisscrossed vents and lighting elements resembling the helmet of Tie Fighter pilot from Star Wars. It's a long, low, and wide ride, with an expansive hood covering a small but strong heart that really sets the A4 apart.

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A V6 engine is available, but 9 out of 10 buyers choose the 211 horsepower turbocharged 2.0 liter 4-cylinder, and that's the A4's competitive advantage. The Audi is the only German luxury sedan available with a 4-pot motor. While a smaller engine may not be a traditional selling point for a sports sedan, the A4 pulls off the inconceivable combination of being the most fuel efficient and quickest entry-level model of the bunch.

In fact, its EPA combined rating of 25 mpg is tops among all conventionally-powered cars in the class, bettered only by the diesel BMW 335d and hybrid Lexus HS 250h. Perhaps more surprising is that A4s equipped with Audi's Quattro all-wheel-drive system are the most fuel-efficient all-wheel-drive vehicles, period (again, discounting hybrids and diesels, actual period.) Those are impressive stats for these frugal times, further supported by a bottom-of-the-pretzel-barrel sticker price of $31,850.

Those numbers, of course, are for A4's equipped with a 6-speed manual transmission. Automatic (Tiptronic) versions are slightly more expensive, and less miserly with fuel (21 city/27 highway), though still tops among self-shifters.

In either case, once you are behind the wheel, such things become unimportant. You sit low in the A4, down where cars used to be before they got jealous of trucks. The center of the hood slopes out of site, while arching fenders rise up to frame your field of vision. The dashboard is cowled and canted with the driver in mind, leaving passengers to gaze wistfully at their chauffeur's environs.

Materials are top-notch across the board, and in black with silver accents very rock and roll, almost like a wall of amplifiers begging for you to plug in and play. The beige and grey color options lighten things up, giving it more of an afternoon tea party feel, but also making the plastics appear cheaper, sucking some of the elegance out of it all.

Technically, the A4 isn't any larger inside than other compacts, but it feels it, especially in the rear. A six-footer can stretch out in front, while another fits comfortably behind, with no knees-a-knocking on the seat back. Interior space was dealt with as efficiently as fuel.

Speaking of which; while the engine may not sound as special as an Audi V8, or even one of its sixes, the 2.0 liter is a pocket Hercules. Power is a little scarce at low engine speeds, but the motor gains momentum like a bungee cord, and by 2,500 rpm is flinging the A4 down the road with great thrust, regardless of the gearbox it is hooked up to. Once underway, the six speeds are well-matched to the turbo's output, allowing for easy passing and relaxed cruising, which contributes to the strong highway fuel economy ratings.

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The manual transmission is particularly rewarding to use, with short, precise throws that are just notchy enough to notice. If the gas and brake pedals were placed any more perfectly they'd be in exactly the same position that they are. Unfortunately, as is often the case in Audis, travel in the clutch pedal is a little off from the other two, but it works well on its own merits. If it's an issue, there's always that automatic.

In either case, the A4 is one of the most well-balanced cars on the road. Not compact sedans: cars. Blindfolded, you'd have a hard time guessing that it is a derivative of a front-wheel drive platform, even after you've recovered from the accident you got in from driving with a blindfold on. The quattro system - which works with traction and stability controls as well as an electronic locking differential system - has a rear bias that endows the car with handling that exhibits Swiss levels of neutrality. Equipped with optional 19-inch high performance tires, the grip is unrelenting, even in the wet.

One thing about the A4 that remains typically German is the cost of its options. The cars that I tested had stickers that were $14,000 and $15,000 above the base price, nearly a 50% increase. The money bought things like Xenon headlights, chrome window trim, heated seats, navigation, and a blind spot warning system that flashes you like a police car if you hit your turn signal and there's someone waiting for you in the next lane. All was appreciated, but most of it unnecessary, though one stood out above the rest.

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This is a luxury sedan, of course, and owners can order up a $2,950 option that offers on-call cushiness known as Audi Drive Select. With it, you can toggle the suspension stiffness, steering effort, and throttle response between Comfort and Dynamic settings either as a group, or individually. Leave it in Auto and the A4 monitors how you are driving and makes adjustments accordingly. Unlike a lot of similar systems, you can really feel the differences, especially in the way the suspension reacts and the weight of the steering resistance. In any setting, the A4 has such quick steering that I had to recalibrate myself every time I got into the car, as it is that much different than 99 percent of what's on the road.

The entire car follows suit in 2010, because not only will the A4 remain the only 4-cylinder German luxury sedan available, but Audi is going to stop offering the 6-cylinder option altogether. So if you want one, you’ll have to get ‘em while they're not hot.

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2009 Audi A4 2.0 T Manual/Tiptronic

Base price: $31,850/$32,700

As tested: $47,400/$46,675

Type : 5-passenger, all-wheel-drive, 4-door sedan

Engine: 2.0L inline-4

Power: 211 hp/ 258 lb-ft

Transmission: 6-speed manual/6-speed automatic

MPG: 22 city, 30 hwy/21 city, 27 hwy

What do you think of the A4?

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