When you're at the top of your game, you have the luxury of making evolutionary improvements instead of radical changes. The Mercedes-Benz S-class has been the best-selling car in its class for decades because it looks good (unlike the BMW 7-series), it has a reputation for quality (unlike Cadillac and Jaguar), and the three-pointed star on its hood is a beacon of status and wealth (unlike Audi). The outgoing S-class, codenamed W220, wasn't the best car in class to drive (stand up BMW 7-series), and its interior wasn't spectacular (that would be the Audi A8). But it did everything pretty well and nothing particularly badly.

So it should come as no surprise that the new S-class (code name W221 for the short-wheelbase model and V221 for the long-wheelbase model) is not a radical departure from the old. Crisper lines, a Maybach-style two-tiered rear, and faux-pontoon fender flares distinguish the new S-class, but you'll have to forgive the unwashed masses for not noticing the difference. Unlike the current BMW 7-series, this S-class doesn't polarize; it just looks nice. Everything's grown an inch or so: the length, the height, the width, and even the wheel diameters, which now start at eighteen inches in the U.S. While the outgoing model was offered with short and long wheelbases, the new S-class will come to the U.S. only in stretched form.

Inside, the gear selector has moved up to the steering column where it appears as a BMW 7-series-like toggle stick. In its former place on the console is an aluminum dial that looks suspiciously like an iDrive controller. You know the one, that stupid little rotary encoder that BMW introduced in the 2002 7-series that requires the hand-eye coordination of a Jukebox Hero and is about as popular as Foreigner's latest album. In the S-class, the dial adds a new dimension of complexity to the Comand infotainment system that's been baffling owners since its debut six years ago. Mercedes is quick to point out that its system has more so-called hard buttons--single-purpose physical clickers--than iDrive, but a quick stint behind the Comand wheel reveals that the system is similarly annoying for all but the most basic functions.