The A4 is Audi's counterpoint to the BMW 3 Series, and it's clearly competitive in the quantifiable, objective measures. Much of the subjective and visceral is present and accountable, too. Even where it follows a different track, it doesn't stray too far. But in one, hugely significant measure, it's far ahead. Audi's Quattro system is almost legendary. The BMW 3 Series and Mercedes C-Class offer all-wheel drive, but Audi remains the benchmark in sporty sedan all-wheel drive. Meanwhile, the Acura TL and many of the other cars that compete in the sporty, near-luxury class only come with front-wheel drive.

The Audi engines employ the latest technology in engine management, phased intake runners and variable valve timing, to boost horsepower and flatten the torque curve, making the power more usable over a wide range of speeds and the engine more responsive to the driver's right foot. The 2.0T and 3.2 engines use a new type of fuel injection called direct injection, which pumps the fuel directly into the cylinder, instead of into the intake runner where it would haphazardly mix with the air on the way to the engine cylinders. This new system allows more precise metering of the fuel and the timing of its introduction as well as a better blending of the fuel and air, all of which combines to yield more efficient combustion. With this system, both engines not only make more horsepower and more torque than the smaller engines they replace, but also get the same or better fuel economy.

The 2.0T four-cylinder engine works best with the six-speed manual gearbox. The 2.0T suffers some turbo lag, and this is exacerbated by the Tiptronic automatic. Likewise, the Multitronic CVT continuously variable transmission with the four-cylinder and front-wheel drive is a competent package, but it's a combination that doesn't deliver what we look for in an A4. There's not a lot of power down at the very bottom of the rev range. Even with the manual, passing a train of cars on a two-lane road can be a challenge. It's just not that good for squirting at a moment's notice. It's great for winding roads, however, and we had a blast with it on a winding hillclimb out of California's Carmel Valley on the way to Laguna Seca Raceway. The 2.0T also does very well on the highway and feels comfortable cruising at high speeds all day. We did this and got 27 miles per gallon. An A4 2.0T Quattro is EPA-rated to get 22/31 City/Highway mpg. The shift throws in the manual could be shorter, and one tester found the path from second gear to third gear a bit notchy.

The 3.2-liter V6 is smoother and more refined than the 2.0T and it works much better with an automatic transmission.

The six-speed Tiptronic automatic is almost as responsive as the six-speed manual and by far the more accommodating in day-to-day traffic. It works especially well with the 3.2-liter V6. We prefer to just put it in Drive and go. Most people will do that and never have anything but good things to say about this transmission. The Tiptronic falls a bit short in the sporty, manumatic game, though. An algorithm in the powertrain management computer shifts up a gear when that will put the engine at the optimum point in the torque curve, and a button beneath the gas pedal shifts down a gear when mashed, say, when passing on a grade. This is all fine and good as far as an impressive application of computerization is concerned, but it mocks the Tiptronic's promise of a manual-override automatic. In practice, the downshift is occasionally helpful, but the upshift is disconcerting when it occurs in the middle of a corner. On the other hand, we're nitpicking here, and the Tiptronic's manual feature works great for holding a lower gear on a grade.

Steering response is crisp, with comforting directional stability. Ride and handling with the base suspension is firm, not stiff. The optional sport suspension tends more toward stiff, almost harsh, although not quite in the kidney-belt range. With either, there's little pogoing over undulating pavement on fast and narrow winding roads. Quick left-right-left transitions are handled with finesse. The same goes for the Avant. The V6 models, which weigh in about 150 pounds heavier, feel a mite less agile and a tick or two slower in response to driver inputs. All models, both sedan and Avant, and regardless of powertrain, feel planted and confident at speed, even into the low three digits.

The brakes offer impressive stopping power and we noticed no fade. Smooth stops can be a challenge, however, almost as if all the electronic systems are confusing each other. The brake pads seem to continue pressing against the discs even as the pressure on the pedal is eased.

Wind and road noise is nicely filtered in the sedan, less so in the Avant, where the large cargo space amplifies the hisses and rumbles. The same large volume of air works well with the stereo, however, giving the bass tones a nice resonance.