At first glance, it may appear as though the 2010 Audi A4 lineup has been eviscerated. The convertible is gone, and so is the V6 -- what's next, cloth upholstery and crank windows? In actuality, though, there are perfectly good explanations for both developments. The good folks at Audi haven't lost their minds, and the 2010 A4 remains an eminently desirable sport sedan/wagon with arguably the nicest interior in this segment.

Now for the explanations. Let's start with the convertible. Last year's A4 drop top was an outdated design based on the previous-generation A4, so its torch has been passed to the foxy new A5 Cabriolet. As for the pricey V6, it couldn't even outperform the base turbocharged four, so Audi will henceforth send its new supercharged S4 (reviewed separately) into battle against upper-crust contenders like the BMW 335i, while the four-cylinder A4 2.0T will continue to lock horns with entry-level sport/luxury cars like the BMW 328i and Mercedes-Benz C300. See? It all makes sense. All is well in Ingolstadt.

One thing that hasn't changed about the A4 is its precise and balanced handling, which combines with its slick styling and upscale cabin to provide an undeniably premium driving experience. Indeed, the only pressing question about the 2010 A4 is whether that four-cylinder engine is up to the task given that most of its rivals offer smooth six-cylinder power. To be fair, the A4's turbocharged 2.0-liter four puts up competitive acceleration numbers despite its cylinder deficit. Yet the only luxury cars of this sort with four-cylinder power are ones on the fringe like the front-wheel-drive Acura TSX.

Otherwise, the 2010 Audi A4 is clearly one of the front-runners in this segment. We'd still recommend that A4 shoppers take a close look at the competition, including the aforementioned 328i (the only direct rival available as a wagon) and C300 as well as the Infiniti G37. Budget-minded shoppers might want to look at Volkswagen's Passat, which is available as a sedan or wagon and offers a detuned but still sprightly version of the A4's turbocharged four. So does the sleek Volkswagen CC, which also features a V6. But if you're after a premium sport sedan or wagon with an appealing mix of style and substance, you can't go wrong with the 2010 Audi A4.

The 2010 Audi A4 is a four-door compact luxury vehicle available in two body styles: sedan and wagon (Avant). The base A4 trim level is the sedan-only 2.0T FrontTrak, which comes with -- you guessed it -- front-wheel drive, as well as a continuously variable transmission (CVT). The other trim level is the 2.0T Quattro, which comes with all-wheel drive and is available as either a sedan or a wagon.

Standard features are clustered into three packages: Premium, Premium Plus and Prestige. Note that the base 2.0T FrontTrak is not eligible for the Prestige package, whereas the 2.0T Quattro is eligible for all three. The standard Premium array includes 17-inch alloy wheels, foglamps, an electronic parking brake, a sunroof, air-conditioning, power front seats with driver lumbar, a leather-wrapped multifunction steering wheel, leather upholstery, cruise control, a split-folding rear seat, Audi's second-generation MMI system (mounted to the dash) and a 10-speaker CD audio system with a subwoofer, satellite radio and an auxiliary audio jack.

The Premium Plus adds bi-xenon headlamps, LED daytime running lights and taillights, rain-sensing wipers, Bluetooth phone connectivity, three-zone automatic climate control, heated front seats and an iPod jack. The bank-breaking Prestige ups the ante with 18-inch wheels, keyless entry/ignition, auto-dimming rear and side mirrors, a navigation system with real-time traffic and the third-generation MMI interface (center console-mounted with revised menus and a joystick-like button atop the control knob), an upgraded 14-speaker Bang & Olufsen sound system (optional on Premium Plus) with a six-CD changer, and voice control for Bluetooth, stereo and navigation functions. Premium wagons add a power tailgate.

The optional Sport package adds firmer suspension tuning, sport seats and high-performance tires, while the S line package for Prestige models is essentially an upscale Sport package. Other options include the navigation system and third-gen MMI (for Premium and Premium Plus trims), adaptive cruise control, a choice of wood trims, a blind-spot monitor, rear-seat side airbags and, a "Drive Select" system (Prestige only) that provides adjustable suspension/steering/transmission response. A Bluetooth/HomeLink bundle is available on Premium models.

The 2010 Audi A4 is powered by a turbocharged 2.0-liter inline-4 that generates 211 horsepower and 258 pound-feet of torque. Front-wheel drive is standard on the base 2.0T FrontTrak, as is a CVT. The 2.0T Quattro comes standard with a six-speed manual and is eligible for an optional six-speed conventional automatic with manual shift control.

At our test track, an A4 2.0T Quattro sedan ran from zero to 60 mph in a satisfactory 6.5 seconds with the automatic. EPA fuel economy estimates for the A4 2.0T FrontTrak are 23 mpg city/30 mpg highway and 26 mpg combined, while the A4 2.0T Quattro comes in at a still-respectable 22/30/25 mpg with the manual transmission and 21/27/23 mpg with the automatic.

All 2010 Audi A4s come standard with antilock brakes, traction control, stability control, front-seat side airbags and full-length side curtain airbags. Rear-seat-mounted side airbags are available as an option in both the sedan and wagon. A blind-spot warning system -- "side assist" in Audi's parlance -- is available as long as the navigation system has been selected. Also optional is an "Active Braking Guard" feature that's part of the adaptive cruise control. If an imminent collision is detected, the system alerts the driver and primes the brakes for full stopping power.

In government crash testing, the A4 received perfect five-star scores for both front and side impacts. Likewise, in Insurance Institute for Highway Safety crash tests, the A4 earned perfect ratings of "Good" in both frontal offset and side impact crash testing, and that was without the optional rear-seat airbags. An A4 Avant with the Sport package we tested braked from 60 mph in an astoundingly short 103 feet -- just 5 feet longer than the Nissan GT-R supercar. Without the Sport package, an A4 Quattro sedan stopped in an average but still acceptable 123 feet.

The 2010 Audi A4's handling is neutral and secure, especially when equipped with the Quattro all-wheel-drive system. It becomes downright athletic when you add the Sport package, though ride quality suffers -- for family use, you'll want to stick with the base suspension.

The now-standard 2.0T engine is a mixed bag. It gives the A4 class-competitive acceleration, but it sounds more like a Civic's engine than a luxury car, and it transmits some off-putting vibrations through the steering wheel.

Also of note is the optional Audi Drive Select system, which allows the driver to choose among three modes for ride compliance, steering effort and transmission responsiveness -- or enjoy custom settings via a fourth "Individual" mode. It's an interesting idea, but in testing we've noted that it's pricey and can be finicky to use. Most shoppers will find the A4's standard suspension, steering and transmission calibrations perfectly adequate.

The 2010 A4's cabin is one of the nicest in this class. The control layout is attractive, if rather button-happy, and the standard leather upholstery trumps the leatherette in base BMWs and Benzes. The dashboard materials are mostly upscale, though we're not fans of the tacky silver plastic trim piece surrounding the gauges and the top of the center stack. At any rate, we find the overall design to be more visually interesting than most other competitors have to offer.

The MMI controls are conveniently arrayed around the console-mounted gearshifter on models equipped with the navigation system. However, the controls are mounted on the center stack in navigation-less sedans and wagons, and reaching forward to operate them is a hassle. MMI is also the newer, improved version with navigation. Other controls are generally intuitive and well laid out, though accessing certain features can be an exercise in frustration. Adjusting something as simple as the fan speed, for example, is a two-step process.

Trunk space in the sedan is listed at a whopping 16.9 cubic feet, huge for this class and sizable even by family sedan standards. The wagon has barely more room behind the rear seats at 17.3 cubic feet, but fold those seatbacks down and you've got 51 cubic feet -- not impressive for a wagon (blame the Avant's rakish rear-end styling for that), but still useful for hauling purposes.