Used 2008 Mercedes-BenzSL-Class 5.5

Exterior & Styling
The basic shape of the SL-Class has been around since the 2003 model year, and it remains one of Mercedes-Benz's most stunning designs. Low and wide, the SL550 doesn't follow other cars on the road, it stalks them. Mild trim changes for 2007 include new chrome-ringed fog lamps and new taillights. The front fenders and hood are accented with silver-colored strakes.

The SL550's retractable hardtop can lower in about 13 seconds, and it's something to watch as the hydraulic system transforms the car from an all-weather touring car into a roadster. Though the fabric roofs of newer soft-top convertibles look fairly graceful, it's hard to beat the sleek coupelike silhouette of a retractable-hardtop convertible. Front and rear parking sensors are optional.

Ride & Handling
The SL550 has a four-wheel independent suspension that features Mercedes-Benz's Active Body Control active suspension technology. The hydraulic system is designed to eliminate body roll, acceleration squat and brake dive, and includes a Sport mode. I drove the SL550 on many different kinds of surfaces — smooth and rough asphalt, concrete highways, muddy logging trails (just kidding, Mercedes) — and found much to like about the roadster's ride quality.

Body roll is nearly nonexistent in the SL550. Switching between normal and Sport modes didn't alter my seat-of-the-pants impressions, though Mercedes-Benz claims the Sport setting further reduces roll and firms up the shocks. Big bumps can make the car hop sideways ever so slightly, but the suspension — though firm — never lets the ride become harsh.

Even though the SL550 has fairly light steering effort for a sports car, the speed-sensitive rack-and-pinion system's telepathic responses and road feel won me over. The wide 18-inch tires sometimes tug at the wheel when driving on rutted roads, but the setup is otherwise hard to fault.

Going & Stopping
It's easy to love the SL550's 5.5-liter V-8. New for 2007, the easy-revving engine makes 382 horsepower at 6,000 rpm and 391 pounds-feet of torque at a low 2,800 rpm. It delivers waves of effortless power at any speed drivers are likely to encounter in the U.S. Mercedes-Benz says the sprint from zero to 60 mph takes 5.3 seconds.

With so much power on tap not far off idle, I can understand why the seven-speed automatic transmission — which includes a Comfort mode that starts the transmission in second gear (to lower engine rpm when accelerating on slick roads) and a Sport setting that starts it in first — has been programmed to upshift rapidly through the gears as the car gains speed; even in the higher gears the engine manages to pull strongly. However, I think Mercedes went a bit overboard. Though the quick upshifts can save fuel and make for quieter operation, they sometimes leave the engine bogged down in too high of a gear when rapid acceleration — or just a not-so-cheap thrill — is needed. To avoid this, I found myself using the automatic's clutchless-manual mode more than I do in most cars just to keep the engine's abundant power available.

The front vented and cross-drilled brake discs measure nearly 14 inches in diameter and are squeezed by four-piston calipers. The rear discs measure 12.6 inches across. It takes a day or two to get used to the sometimes nonlinear pedal response of the electrohydraulically actuated brakes, which at times provide immediate stopping performance but can also startle the driver. There were occasions when I pressed the pedal and nothing happened until I pushed it farther down — not a sensation you want when you're piloting a six-figure sports car through heavy traffic.

The Inside
Sliding into the driver's seat requires clearing a substantial chrome door sill. It's also a bit difficult to extract yourself from the car, but no more so than in other sports cars.

Though it's not cramped, the SL550's two-person cockpit is definitely intimate. I'm 6-foot-1 and was able to get comfortable in the car, but could tell I was nearing the constraints of the cabin when attempts to move the driver's seat farther backward resulted in the backrest tilting forward without my help.

My test car had the optional dynamic multicontour seats, which include all sorts of fancy adjustments, like a power height-adjustable head restraint, power-adjustable side bolsters, a power-extendable seat cushion and a massage setting. These seats have firm cushioning and are highly supportive. They're covered in soft leather, as are the steering wheel, dashboard, center console and doors. Hand-polished wood trim is standard. Overall, it's a beautifully crafted space.

Mercedes-Benz's Comand navigation and audio system is standard and features a dash-mounted information screen. Instead of a touch-screen interface, selections are chosen via buttons on the side of the screen that correspond to the current menu. I didn't find it as intuitive as competing touch-screen systems, but it should help prevent the screen from getting fingerprints and smudges on it. Dual-zone automatic air conditioning and a power tilt/telescoping steering wheel are standard. Adaptive cruise control and a fixed glass roof with a sunshade are optional.

Safety
Neither the Insurance Institute for Highway Safety nor the National Highway Traffic Safety Administration have crash tested the SL550, and it's unlikely either will in the near future, given that it is a low-volume model. Standard safety features include antilock brakes with brake assist, side-impact airbags in the doors, a driver's knee airbag, a popup roll bar, and an electronic stability system.

Cargo
There's a respectable 10.2 cubic feet of cargo room with the top up, and lowering the hardtop only takes away about 3 cubic feet of room. The trunk features a movable divider that shows how much luggage you can safely pack without intruding on the space reserved for the stowed roof panels when the top is down. A power trunklid is optional. Though the roof panels take up trunk space when lowered, they can motor upward when the lid is opened, allowing access to the space below the divider. Some retractable hardtops trap cargo underneath the lowered roof.

SL550 in the Market
Even in this rarified market segment, the SL550 faces plenty of competition from sports cars like the Cadillac XLR retractable-hardtop roadster and soft-top models like the Jaguar XK convertible and upcoming Aston Martin V8 Vantage roadster. The only thing that really dampens my enthusiasm for this model is its troubled reliability history, because a service department waiting room is no place to be when you own a car like this.