Audi S8

The Audi A8 took the long road in becoming a legitimate competitor for the full-size sedans from Mercedes-Benz and BMW. When it made its debut with an optional W-12 engine and its aluminum space frame, we were dazzled. But it's the current generation of the A8 that truly stands out as a fully realized contender in the niche. The Mercedes-Benz S-Class still stands at the front of the line in the segment, and the 7-Series isn't trailing far behind–but the A8 offers a set of interesting drivetrains and an abundance of technology to help sway shoppers toward the rings rather than the star or roundel. It's a real player in the segment now–competing happily at virtually every level–and even winning some of the categories along the way. With the A8, Audi's fielded a sedan with arguably less compelling looks than its own lissome A7 hatchback. But the job of a German full-size four-door isn't to draw stares, it's to avert gazes. The details do the talking: the LED running lights and taillamps are heirloom-quality, all models now include full-LED headlights, and there's not much other jewelry laid out for public inspection. It's inside where the Audi hides its wealth: the cockpit's lavish in a restrained way, with hides and wood and aluminum and even carbon fiber laid side by side, radiantly and so carefully, the sueded headliner takes some time to pick up. The usual A8 lineup of V-6, V-8, and W-12 engines has been joined by a V-6 turbodiesel with outstanding economy and very good performance. It adds a useful dimension to the A8, a blast of 800-mile-per-tank, 36-mpg practicality to an $85,000 sedan that bolds and underscores Audi's commitment to diesels. All the other powertrains offer better acceleration and qualitative performance, outside of fuel economy: of them, we'd opt for the S8's revtastic twin-turbo V-8 and its 520 horsepower over the 333-hp supercharged six or the detuned 435-hp twin-turbo V-8. There's also the patriarchal W-12-powered car, with 500 hp, and it seems decadent in a car intent on being less conventional and more thoughtful. A well-calibrated eight-speed automatic and all-wheel drive are standard equipment on every A8, and the combination accent its surefooted feel. It's light to the touch until you make it not so via Audi Drive Select, the electronically calibrated, driver-adjustable system that governs powertrain, steering, and suspension feel. Drive Select gives drivers the choice of Dynamic, Comfort, Auto, or Individual modes. Overall, it's an excellent setup that brings out the best in this big sedan, whether you're in tight switchbacks or cruising on the highway. The only letdown is that the steering feel (or lack thereof) leaves enthusiasts much to be desired. The A8 now comes to the U.S. only in extended-length A8 L models. It was our favorite anyway, as it offers five inches of additional wheelbase and overall length, most of which is aimed at rear-seat passengers. Trunk space is abundant as well. Included on the W12 and available on V-8 models are lavish individual seats in back that