The technology packed into the new S550 is impressive, if a little daunting to use. Shifting is done via a stubby lever on the steering column. Tap it down to set the buttery, seven-speed automatic transmission in motion. Tap it up for reverse, and push a button on the end for park. As with high-end BMWs and Audis, the navigation system, the 14-speaker Harman Kardon surround-sound system, and other functions are controlled by a computer-mouse-like knob on the center console, which you use to course through menus on a screen. It's confusing at first but easy to master with a little effort, and there are buttons to override many of the screen commands if you really get lost.
The S550's ride is exceptionally smooth, largely because of an electronic damping system that easily absorbs even major potholes. For an extra $3,900, you can add Active Body Control, which steadies the ride even more during cornering and braking. The front seats have bolsters that expand to snug you in during sharp turns and a massage function to work the kinks out of your back during long drives.
There's even optional infrared night vision, which displays an image of the road up to 500 feet ahead on a screen that appears where the speedometer normally is. The resolution is good enough that you can read street signs, and Mercedes says it will cut through rain, snow, and fog. About half of all customers so far are taking the $1,775 option.
The new model is pricey, even against rivals. The S550 starts at $86,175 (vs. $72,495 for an '06 BMW 750i and $68,850 for an Audi A8). Mercedes also needs to demonstrate that it has solved the quality problems that plagued the previous generation of the car. But the early line on the new S550 is that it's way better than the model it replaced and a match for any comparable luxury car. By Thane Peterson