The system understood our voice commands with no problem, and programming destinations using the COMAND knob worked just as effectively. While in full-screen map mode, the system also displays the scale, the compass heading, the current latitude and longitude, and the number of available satellites--in case we were curious.
For the nitpicker, the one drawback on the 2007 Mercedes-Benz S550 is that telephone integration requires more than a simple Bluetooth pairing. Bluetooth is available in the S550 but only to read address-book info from a phone, a PDA, or a laptop, not to make calls. Cell phones must be placed in a model-specific cradle in the center armrest and, once in place, are fully accessible both directly and through a keypad hidden under the padded wrist rest.
Clustered around the COMAND knob are 10 switches for sundry technical tasks, including alternating between interior systems and switching from Comfort to Sport suspension mode and various radio controls. One button is left to be customized for a radio function of the driver's choosing.
Power rear seats cost $1,120, and the panorama sunroof is a $1,000 option. Our car also had an intuitive rearview monitor system, which offers helpful distance and intended path markings, for $750. Rear side-window blinds are power operated from the driver's or rear seats for $700. Satellite radio prep is $500, four-zone climate control goes for $1,200, and the night-vision option is $1,150. The base price of the Mercedes-Benz 2007 S550 ($85,400) is actually slightly lower than that of its predecessor, but it's easy to see how a six-figure bottom line soon racks up.
Mercedes calls its newest 5.5-liter V-8 a new-generation engine, convenient marketing jargon that abandons its long-defended single-cam, V-8 layout in favor of a dual overhead-cam unit. The result is a stout 382 horsepower at 6,000rpm, with the peak 391 pound-feet of torque available from 2,800rpm to 4,800rpm. These power figures are substantial increases over the outgoing S-Class V-8's numbers, yet emissions have also been reduced, with help from variable valve timing.
On the 2007 Mercedes-Benz S550, power goes to the rear wheels through a seven-speed automatic transmission. Buttons on the back of the steering wheel allow manual shifting, but the broad power band and the number of available gear ratios mean that acceleration is brisk from any speed, and picking gears manually is redundant--more for play than performance. Mercedes-Benz's official 0-to-60mph time is 5.4 seconds, very quick for a 4,270-pound car.
Our test car's single most expensive option was Active Body Control (ABC), at $3,900. It consists of hydraulic pistons at the top of each wheel's coil spring and is controlled by a computer monitoring 13 sensors: 4 in the wheels to gauge level and 9 around the body to detect movement. New data is read every 10 milliseconds, with suspension damping updating accordingly every 120 milliseconds. It was difficult for us to judge the system's real-world effects without having driven a non-ABC-equipped version, but as with the BMW 750Li's roll-bar twisting system, body roll is almost fully eliminated. Its contribution to ride comfort was very noticeable over rough San Francisco streets, where the S550 seemed to float over potholes. Speed-sensitive power-assisted steering melds well with ABC, never feeling overboosted and maintaining good feedback at all speeds--no mean feat in a car more than 17 feet long.
The 2007 Mercedes-Benz S550 is EPA-rated at 16mpg in the city and 24mpg on the highway. According to our test car's trip computer, it had averaged 17.7mpg at an average speed of 29mph during its previous 1,613 miles.
With the possible of exception of a few 6,000-pound leviathans on the current SUV market, the 2007 Mercedes-Benz S550 has to be considered the safest passenger car on the road. Most of the active safety features are available in similar guises in other cars, but the S550 integrates them in a unique manner.
Compared with earlier heat-based systems, the S550's night-vision assist is much more effective at detecting objects up to 500 feet ahead and providing a clear picture with no washout from oncoming headlights.
One of our favorite safety features was the Distronic system's radar sensors, which allow the 2007 Mercedes-Benz S550 to prepare for impending collisions in innovative and unprecedented ways. While seat-belt tensioning in preparation for impact is nothing new, the S550 can also move its seats to optimize air-bag effectiveness and adjust seat bolsters to hold occupants more tightly. (The current BMW M5 also features active seat bolsters for hard cornering, but they are not integrated with any collision-detection systems.) The front and full-length side curtain air bags therefore have an extra split second to deploy before a crash. The car's windows and sunroof are also closed if a possible impact is anticipated, reducing the risk of injury to those inside. If the radar detects that heavy braking is needed, it warns the driver while prepressurizing the brake system in anticipation of an emergency stop. ABS is standard, as has it been since the S-Class was the first production car to offer it in 1978.
Other more familiar but no less-important safety offerings include a tire-pressure monitor, which displays each tire's reading on a speedometer-overlaid readout; a front-passenger occupancy sensor; the Tele Aid system to call for help in the event of theft, being locked out, or a collision; and electronic stability control.
The warranty period for the 2007 Mercedes-Benz S550 is four years/50,000 miles, including 24-hour roadside assistance.