2007 Mercedes-Benz S550

Traffic on the Hollywood Freeway is moving as slowly as salmon swimming upstream after watching a salmon documentary, and for once that's a good thing. The relentless stop-and-go is the perfect opportunity to let Mercedes-Benz's brand-new flagship sedan, the 2007 S550, show what it can do. You can read about the dragstrip and the slalom cones later; right now, the big Benz is putting on a truly unforgettable performance: It's driving by itself.

Ooohh! Aaahh! Well, okay, we're helping a little--our eyes are watching the road, and our hand is nudging the steering wheel. But for the past 45 minutes or so, our feet haven't touched the pedals. The S550 is keeping pace with traffic--accelerating, slowing, even braking to a complete stop and then accelerating again--all on its own. The new S-Class is the first production automobile in the world capable of doing this. For those who remember when the idea of a robot driver was the stuff of science fiction, welcome to the future. And, by the way, HAL 9000's real name is "Distronic Plus."

Mercedes is making one giant leap with this flashy, technology-packed new edition of its iconic sedan. Not only does the 2007 S-Class represent a significant advance in automotive wizardry, it's also a radical departure from the stoic, conservative big Benzes of yesterday. Call it engineering chutzpah, call it engineering arrogance, but Mercedes is boldly going where no automaker--not even BMW--has gone before. The market will ultimately decide whether the company is going in the right direction, but after living with the car for two weeks in L.A. and conducting an extended round of detailed instrumented tests, our impressions are decidedly mixed.

In general, the 2007 S-Class, in dealerships this February, is everything you'd expect an all-new model to be: bigger, roomier, stiffer, more powerful, and more efficient than the car it replaces. Impressively, at a preliminary base price of $87,175 (final figures hadn't been set at press time), the S550 is about $1650 less than the outgoing S500. With a wheelbase stretched more than three inches over the old S (Mercedes will sell only the long-wheelbase version of the new car in the U.S.), the S550 provides limolike rear-seat room (although the competition is plenty roomy, too--see accompanying sidebar chart). The cockpit is gorgeous, with the rich ambiance of a Feadship yacht and such luxurious details as real aluminum switches and soft lighting that glows along the glossy woodwork.