2007 Mercedes Benz S550 AMG

Tally all the engine possibilities and it's accurate to say that Mercedes-Benz currently offers-whoa!- 43 models. Ask the average schmo on the street to name the most famous, and he might say, "McCambridge, " or he might say, "Gullwing, " but he'll probably say, "S-class." For more than 50 years, S-class Benzes have been the most succulent sausages in the Teutons' tray of vehicular sauerkraut.

For 2007, the S-class lineup has been simplified. No more short- and long-wheelbase cars, just the 124.6-inch edition, 3.1 inches more majestic than its predecessor. The lineup now comprises the S550 tested here, whose $86, 175 base price is actually $1650 shy of its S500 forebear's, followed in April by a 510-horse V-12 S600, with a sticker close to $130, 000. An all-wheel-drive S550 4MATIC should arrive in November, and the inevitable AMG variants will manifest when AMG and every F1 driver on the planet are damn well ready.

Apart from the S550's swollen fender haunches-reminiscent of those hockey-puck shoulder pads that Larry King jams into his suits-what you notice first about this car is its seats. Really. They're sumptuous without being saggy and offer 14-way "multicontour" adjustments that can even change the distance the cushion extends beneath your thighs, and there are optional multilevel fans blowing cold or hot winds up your keister, and there are side bolsters that suddenly stiffen in reaction to cornering forces, and there are center lumbar chambers that expand and contract to change your position twice per minute, and there's even a vigorous Magic Fingers option that feels like small pine logs rolling slowly down the sluiceway that is your spine. We drove this S550 from Manhattan to Ann Arbor, stopping only to replenish 23.8 gallons of premium unleaded, and felt as if we should have continued on to Iowa. Similar praise can be heaped on the vast and comfy rear chairs, where you can tuck your loafers beneath the tall front seats, spread out, and fully open the Times' Arts & Leisure section. These new seats are so good that they bear the seal of approval of the Aktion Gesunder Rücken, which is either a German outfit that rates products for spine-friendliness or a bunch of guys who look for life forms under rocks.

In the past, Mercedes expended a moderate load of warm air hyping its SOHC three-valve-per-cylinder V-8s but now has fast-forwarded to the world of twin-cam four-valvers, with superlative results. This new variable-valve-timing V-8 purrs out 382 horses at 6000 rpm but stockpiles all 391 pound-feet of its peak torque right there on the bottom shelf, ever accessible from 2800 to 4800 rpm. The engine is as smooth as a poetry major on Ambien-more than once we tried to start the bugger while it was running. Unlike your average poet, however, it is practically mute. In fact, the S550 is quieter at idle, at full throttle, and at a 70-mph cruise than a Bentley Continental GT and is exactly as quiet at 70 mph as that perennial exemplar of soporific tranquillity, the Lexus LS430.