The S-Class is made up of the S550 models, which come with a V8 engine, and the S600, which comes with a turbocharged V12. The S550 4MATIC adds the all-weather capability of all-wheel drive. Two AMG versions bring racecar performance to this big luxury sedan.

All of them boast quick acceleration and are comfortable and stable at high speeds. Performance goes up with the more powerful engines, of course. The S600 can accelerate from 0-60 mph in about 4.5 seconds, according to Mercedes, which is very quick indeed.

These cars handle remarkably well for big luxury sedans. They are responsive but not darty. The Airmatic air suspension system is tuned toward the sportier end of the spectrum. The Automatic Body Control active suspension option cuts body roll significantly, and you can really feel it working when you throw the car into a fast, sweeping downhill curve. And we found the Brake Assist Plus brakes spectacular in their stopping power and stopping distance performance.

For 2009, all S-Class models get heated and active-ventilated front seats, a wood-and-leather steering wheel, a power trunk lid, shift paddles (replacing smaller buttons) on the steering wheel, and push-pull power window switches. The optional Distronic Plus cruise control now includes Blind Spot Assist and radar-type Park Assist. And new 18-inch alloy wheels with seven double spokes enhance the look of the base S550. The current generation dates from 2007, when the S-Class was completely redesigned with larger dimensions all around and dramatic fender flares that make the big Benz look aggressive.

S550 models are powered by a 5.5-liter V8 and come with a seven-speed automatic transmission; the 4MATIC adds all-wheel drive. The S600 is powered by a 5.5-liter 3-valve V12 twin-turbo engine connected to a heavy-duty five-speed auto. The federal Gas Guzzler Tax adds $1,000 to the S550, $1,300 to the S550 4MATIC, and $3,000 to the S600. The S63 AMG is powered by a 6.2-liter V8, while the S65 AMG features a 6.0-liter V12.