BMW and Mercedes-Benz continue to be the front-runners in the luxury segment; yet Audi has been edging up surprisingly close. And what Audi still might be missing in cachet, it makes up for with charm--demonstrated well with its smart, thoroughly competitive A4.
The A4 is at its simplest the brand's bread-and-butter model, sitting in the lucrative and popular entry-luxury sedan segment. On the outside, it can feel understated where the Mercedes-Benz C Class is brash and the BMW 3-Series is bold; inside, the A4 is an entry-level tailored suit, perhaps a half-step behind what you can get in the latest 3-Series, if you pay quite a bit extra. But behind the wheel, the A4 is poised, and satisfyingly capable, landing somewhere between plush and focused.
It's this balance that gives the A4 its charm, and it's that balance that makes it a serious rival to the 3-Series, even though BMW sells more cars. Under the hood, the base A4 soldiers on with its '2.0T' 2.0-liter turbocharged engine--a move made well before BMW's addition of the turbo four in the 328i model. With 211 horsepower and 258 pound-feet of torque, it's closely matched to the 3-Series, though it ultimately comes up 29 horsepower short. For 2013, BMW has also introduced the 200-hp 320i, with a lower-output version of the 328i's engine--and that should be a closer match to the A4 2.0T.
Unlike the 3-Series, however, you won't find a potent six-cylinder in the mid-range; you have to jump all the way up to the S4, where you'll find a 333-horsepower supercharged V-6 engine, an aggressive suspension, and rakish styling that rivals the M3's, though again, the Audi comes up short on power numbers--the M3, still riding on the last-generation chassis, generates 414 horsepower from a 4.0-liter V-8. BMW, on the other hand, offers the 335i, with a turbocharged in-line six-cylinder good for 300 horsepower and 300 pound-feet of torque. The Coupe and Convertible versions of the 3-Series also continue forward on the last-generation chassis, but offer the 335is trim, which packs an even more potent 3er.
Also unlike the 3-Series, the A4 is a front-drive-based sedan, with quattro all-wheel-drive available in higher-trim models. While this bias--and its frontward weight bias--ultimately brings it up somewhat short of the 3-Series' ultimate dynamics, the available quattro system makes the A4 as competent as any luxury sedan in foul weather. BMW's xDrive system is available in the 3-Series, but only in a limited range of trim.
Further distancing itself from the 3-Series, the Audi A4 is available as a wagon--or Allroad, as Audi styles it for the latest model year. BMW is reviving its 3-Series wagon but without the more overt styling cues.
Front seats are spacious and comfortable in both the 3-Series and the A4, though the latest 3-Series sedan grows an inch in wheelbase, dedicating most of that to rear seat space, where it is noticeably roomier than the A4's close quarters, particularly when it comes to leg room. Neither is spacious, however--a classic tradeoff in the segment.
Quality, fit, and finish are very good in both cars, with the new BMW's design among the best in class, though some touches can seem out of character--like the optional nav screen that perches on top of the dash, instead of integrating into it. The A4 is a more seamless piece, with a lush new LCD screen that renders Google Earth and Street View maps in gorgeous detail. For most, it will come down to a matter of taste: where the BMW is sometimes drab, sometimes busy, the Audi is sleek and polished, uncluttered and largely intuitive. Creaks, rattles, and other signs of poor build quality are non-existent in the A4.
When it comes to ride quality, both cars err a bit toward the sporty side, showing occasional harshness over rougher surfaces. Some will call it the price they pay for their sharper handling, but others will find the Mercedes-Benz C Class's slightly more plush ride preferable to either.
Both cars also offer a host of advanced technology, with iDrive powering the 3-Series' infotainment and MMI behind Audi's. While both systems are advanced and capable, MMI is slightly more intuitive to most. On the flip side, the A4 makes some items, like Bluetooth, optional upgrades, while they're standard on the 3-Series. The 3-Series also offers an excellent head-up display (HUD) that's just become available on the A4, tying speed, navigation, and other information into a display projected onto the windshield. Audi also has in-car wireless Internet with Audi Connect, which in turn feeds data to that exceptional nav system.
One bit of technology the A4--and S4--come with that we'd rather it didn't is Drive Select, as system that offers adjustable control of the steering, damping, and other characteristics of the car. It comes off as gimmicky, changing feel but not improving the car's communicative aspects or handling in any noticeable way.