The front of the car thrusts visually forward with prominent grille slats, a deeply wedged hood and fenders that dive steeply into the distinctive headlamp clusters. A deep bumper forms a coupe's characteristically muscular rear, braced by two chromed exhaust pipes.

The CLS features details that reduce noise when cruising at high speed. Look closely and you'll discover things like plastic deflectors in front of the front wheel arches to improve airflow across the front axle links, aerodynamic cladding on the rear axle spring links, and mini-spoilers in front of each wheel to reduce dynamic pressures at the tires and improve airflow around the wheels. Even the wiper arms were refined in the wind tunnel. These aerodynamic wipers feature a mounting system and integrated spoiler for better wiping with less noise.

We're not sure we love the looks of the aggressive lower body cladding on the CLS63 AMG. It's just not as pretty as the CLS550. The staggered-width, 19-inch five-spoke AMG wheels look fantastic. The deep front and rear aprons and sculpted doors sills are anything but ugly, yet they get in the way of the graceful shape.

The AMG version rides a half-inch lower than the standard CLS, but both models cut a fairly slippery profile. A drag coefficient of 0.31 is low for such a sculpted four-door car. This aerodynamic efficiency contributes to overall fuel efficiency and reduces wind noise at high speeds.

Interior Features

Inside, the Mercedes-Benz CLS has the bespoke quality of some of the world's most expensive sedans. This richness flows from good, clever design as much as from the materials used. A driver feels successful at the wheel of the CLS, much as a rear passenger feels in the back of one of Mercedes' mighty Maybach sedans.

The view forward is filled by an expanse of burr walnut that stretches between round vents in the far corners of the dash, finished in a silk matt rather than the high-gloss familiar in many Mercedes. The walnut surface is broken by recessed center air vents, the climate control switch cluster and the main instrument cluster, which features three chronometer-style gauges and two LCD bar graphs for fuel level and coolant temperature. Each gauge is ringed with chrome, as is the cluster as whole. The graphics are crisp, and covered with a special mineral glass that virtually eliminates glare.

Fit and finish is good, and the custom-tailored feel is enhanced by the design. Note how the front passenger airbag door blends perfectly into the upward sweep of the walnut panel. Note how the chrome-and-walnut theme carries down through the center console, with a ring surrounding the transmission shift lever, and into the rear cabin, with a separate walnut panel and chrome trim for the rear-seat climate controls. Note how the curve of the center rear console is reflected in the reverse curve of the outboard armrest.

All four seats are covered in leather, with a thicker, richer Nappa finish in the CLS63 AMG. The standard front seats are adjustable 10 ways, using Mercedes' patented seat-shaped switches. There are three memory storage settings, and they can be matched to the remote key fob. Most switches are conveniently placed. A color display screen incorporates audio controls, navigation system and most other functions into a single set of switches. It takes time to learn, but I prefer it to the point-and-click devices in many luxury cars.

The standard harman/kardon Logic 7 stereo sends 480 watts of audio through 10 speakers, including two in the rear self. Digital processing allows the driver to tailor sound to his or her taste, or to create a surround effect for any seating position. The CLS stereo sounds good. If it doesn't match the best currently available, it's light years better than those in Mercedes-Benzes just 10 years ago.

In the rear seats, the sexy exterior styling results in a decrease in headroom, compared to a Mercedes E-Class. As part of our familiarization with the CLS, we were chauffeured across Rome so that we might see how the rich and famous do it. Tough job. My six-foot frame was comfortable on winding city streets, but passengers much taller may step out of the CLS with a crick in the neck.

There's no problem with trunk space, however. With 15.9 cubic feet of volume, the CLS trunk offers exactly the same space as the E-Class sedan, and not much less than the larger S-Class sedan.

In terms of interior comfort, the CLS makes for a great four-passenger sedan.

Driving Impressions

The Mercedes CLS550 is generally a joy to drive. Its 382-horsepower V8 delivers a wad of acceleration-producing torque at any speed. Its computer-managed air suspension scoffs at whatever the road serves up, delivering that classic Mercedes balance of ride comfort and predictable handling. This car is rock steady and inspires confidence at speeds that could earn you a nice set of handcuffs, courtesy of the highway patrol.

The CLS is loaded with technologies, but they can be a double-edge sword. Two drive-by-wire systems, the throttle/accelerator and brake controls, work to different effect. Both use sensors and servo motors in place of cables, virtually eliminating mechanical parts. The electronic throttle control is fantastic. It delivers instant engine response and integrates with the transmission and cruise-control system for smooth shifts and seamless operation, and it can actually improve fuel economy.