The S-Class is available with a range of V-8 and V-12 engines that produce from 382 horsepower in the V-8 S550 up to 604 hp in the ultimate-bragging-rights sedan: the S65 AMG with a twin-turbo V-12. In between are the S600 with its 510-hp, twin-turbo V-12 and the S63 AMG, which has a 518-hp V-8 under its hood. These are pretty heady power figures for a full-size luxury sedan, but not counting the AMG versions they're relatively similar to what competitors from Audi, BMW and Jaguar offer; big horsepower is a prerequisite in this class.

Even if you choose the "base" S550 with its 5.5-liter V-8, you're still going to be in for a performance treat. This V-8 engine is what you might call a strong, silent type; it's powerful and makes this big sedan lunge forward when you mash the gas pedal to the floor. Mercedes-Benz cites a zero-to-60-mph time of 5.4 seconds for the S550, which is stunning considering the sedan's 4,465-pound curb weight. The more powerful versions are quicker still, with times in the mid- to low-4-second range. That's Chevrolet Corvette territory.

The S550's V-8 drives a seven-speed automatic transmission that, like the engine, performs in a purposeful, quiet way. In many cars you feel when a shift occurs, but in the S550 the only hint that it's happened is when the V-8 gets even quieter with the drop in engine speed. The transmission includes Mercedes' Touch Shift clutchless-manual mode, which lets you select gears by pressing buttons on the back of the steering wheel.

Gas mileage for the S550 is more like what you might expect for a full-size SUV; the rear-wheel-drive S550 gets an EPA-estimated 14/21 mpg city/highway, but with the optional 4Matic all-wheel-drive system it drops slightly to 14/20 mpg. Not surprisingly, it's even lower — 11/17 mpg — if you choose the S600 or one of the AMG models. Most typical car buyers would see this as a significant negative, but here the frequent visits to the gas station are likely to be nothing more than a slight inconvenience for the owner of one of these six-figure cars.