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2015 Mercedes-Benz S550 Coupe review: Too comfortable to stop driving

The new S550 Coupe is more than just a two-door version of the S-class sedan, it brings comfort and luxury to new levels. Too bad its Internet doesn't work.

Wayne Cunningham Managing Editor / Roadshow
Wayne Cunningham reviews cars and writes about automotive technology for CNET's Roadshow. Prior to the automotive beat, he covered spyware, Web building technologies, and computer hardware. He began covering technology and the Web in 1994 as an editor of The Net magazine.
Wayne Cunningham
7 min read

Driving the 2015 Mercedes-Benz S550 Coupe along one of my usual test loops, combining city streets, the freeway, twisty mountain roads and a scenic stretch of coastal highway, I enjoyed the incredibly smooth ride quality and able cornering, the low growl of the engine, and the high fidelity sounds coming from the 24-speaker Burmester audio system. The seats massaged me, and sound dampening created a serene space in the cabin. The S550 Coupe's climate system wafted freshening scents into the cabin air.


2015 Mercedes-Benz S550 Coupe

The Good

The 2015 Mercedes-Benz S550 Coupe's standard air suspension and all-wheel-drive deliver exceptional comfort and confident handling. Driver assist systems make for safer night driving and ease the effort of long road trips. A 24-speaker Burmester audio system creates exceptional fidelity, and this coupe is gorgeous inside and out.

The Bad

Mercedes-Benz took a small step toward redesigning its cabin tech interface, but needs to do more. The Internet features built into the car are nearly useless due to how long it takes to establish an Internet connection.

The Bottom Line

With its stunning looks, the 2015 Mercedes-Benz S550 Coupe sets a new bar for driving comfort, yet can also handle twisty roads with confidence and power. While it carves a path toward the self-driving car of the future, its Internet features let it down.

Outside waited a sunny day with many scenic locations that would provide a perfect background for the S550 Coupe's gorgeously-sculpted body.

But I couldn't bring myself to stop and take photos. The car made me feel too good, too happy to break up the current mood. It was like listening to your favorite song on an exquisite stereo system, which I was, and not wanting it to end. The S550 Coupe is one of the most comfortable cars I have driven, not in the sense of sitting in a really nice chair, but more like piloting a first-class suite that somehow follows your every intention with power and confidence.

2015 Mercedes-Benz S550 Coupe
The Mercedes-Benz S550 Coupe looks beautiful on the outside and is incredibly comfortable on the inside. Wayne Cunningham/CNET

As the name suggests, the S550 Coupe is the two-door version of Mercedes-Benz's flagship S-class. Rather than merely stripping two doors from the sedan, though, Mercedes-Benz designed a coupe that stands on its own. The S550 Coupe comes in 9 inches shorter in overall length and wheelbase than the sedan. The body shows a more svelte appearance, with a lower grille and a wonderful pillarless side graphic. The smaller dimensions do mean very compromised legroom for the two rear bucket seats, so don't expect to be running a limousine service with the S550 Coupe.

Despite the smaller dimensions, Mercedes-Benz reckons it has something special with the S550 Coupe, setting the US base price at $119,900, about $25,000 more than the S-class sedan. The example I drove, outfitted with premium audio, massage seats and driver assistance features, brought the total up to $149,575. Although it features the same driveline in the UK and Australia, Mercedes-Benz calls it the S500 Coupe in those markets, with base prices of £95,035 and AU$339,737, respectively.

2015 Mercedes-Benz S550 Coupe combines exquisite styling with high-tech comfort (pictures)

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Riding on air

Essential to the S550 Coupe's comfort, an air suspension supports the front and rear, delivering an incredibly smooth ride as it dampens the usual bumps and imperfections of the road. Surprisingly, this suspension doesn't make the car feel floaty, or let it wallow. Going over undulations in a road, the S550 Coupe's suspension prevents it from oscillating up and down.

And rather than offering many different drive settings, a button on the console made the choice simple, with either Comfort or Sport.

Sport proved a revelation in the S550 Coupe. Pushing it through a set of tight turns, the big car remained steady, even as I got the tires squealing. The suspension's Sport mode managed to keep the body level, although I could feel the weight, nearly 5,000 pounds, attempting to drag the sizable coupe sideways. As a likely helper, although impossible to tell from the driver's seat, Mercedes-Benz includes its 4Matic all-wheel-drive system as standard. Power shunted to the front wheels likely helped grip in the turns.

Meaty Goodyear Eagle F1 tires combine with an air suspension and all-wheel-drive to give the S550 Coupe excellent handling. Josh Miller/CNET

Another button on the console let me switch the driveline between Efficient and Sport modes. The former toned down the throttle response a bit, but not to such a degree that the car felt anemic. The S550 Coupe uses a 4.7-liter V-8 engine, with direct injection and a turbocharger for each bank of four cylinders. With 449 horsepower and 516 pound-feet of torque, this car showed prompt throttle response in any mode.

Efficient certainly doesn't mean frugal in this case, either, as the EPA fuel economy comes in at 16 mpg city and 24 mpg highway. My average hit the middle of that range, at 19.6 mpg. I wouldn't expect to get better than 20 mpg on a regular basis.

That highway figure looks pretty good for a car this heavy with this much power, and that is largely due to the seven-speed automatic transmission. In the S550 Coupe, and most other Mercedes-Benz models, there is no traditional shifter. I used a stalk on the steering column to choose drive, reverse and park. Steering-wheel-mounted paddles let me choose gears sequentially, but the system wasn't designed to stay in manual mode. When I left off shifting, on a straight, for instance, automatic shifting took over.

2015 Mercedes-Benz S550 Coupe
The heads-up display shows navigation and vehicle speed. Wayne Cunningham/CNET

Although Mercedes-Benz employs a good amount of sound-deadening material around the cabin, including double-glazed side windows, I still heard a low snarl from the engine when I accelerated. I couldn't help feeling that Mercedes-Benz engineered the car precisely so that engine note came through in the cabin, rewarding its buyers with a sense of power.

Big screens times two

Along with inspiring engine noises, a beautifully designed dashboard sweeps across the cabin. And it houses two very long LCDs, one for the instrument cluster and one for infotainment. Unlike in BMW cars, there is no split-screen function on the S550 Coupe's infotainment display, so you are looking at full-screen maps, stereo and phone information.

The interface represents a slight evolution of that which Mercedes-Benz has been using for years. A jog-dial on the console selects onscreen menus, and shortcut buttons take you to major functions. Pushing up the jog dial takes you to an upper menu ribbon, also showing the system's major functions, while "down" takes you to a lower ribbon with specific options for each function, such as choosing a destination in navigation.

This jog-dial controls and selects onscreen menus. Josh Miller/CNET

Prior versions of this interface showed easy drop-down menus for selecting audio sources, phone functions and other options, but Mercedes-Benz replaced those drop-downs with icon-based circular menus. The new treatment looks good on these submenus but isn't in keeping with the menu structure as a whole. Mercedes-Benz really should have given the entire interface a redesign, instead of this partial approach.

I mentioned the spectacular sound of the Burmester audio system previously. The S550 Coupe actually comes standard with a 13-speaker Burmester system, but this car had an audio upgrade to the Burmester 3D surround sound system, giving it 24 speakers with 1,540 watts of amplification. The resulting sound shows incredible fidelity, with tremendous detail and richness in the reproduction.

The car features a good range of audio sources, including Bluetooth streaming, two USB ports that also support iOS devices, an onboard hard drive, an SD card slot, satellite radio and HD radio on both the AM and FM bands. While the music library interface for devices plugged into the USB ports was very usable, Bluetooth streaming in this car remains a dumb connection, merely streaming audio to the stereo and requiring you to use the actual phone to select music.

Mercedes-Benz includes the TuneIn app built into the the car, which lets you access thousands of online radio stations from around the world. And other native apps let you search for destinations and find information about a location, however I found them completely useless due to the extraordinary length of time the car takes to establish an Internet connection. The car's dedicated data connection proved its major failing, a surprising miss amidst all this opulence.

The interior design looks just as good as the outside. Josh Miller/CNET

Where the S550 Coupe doesn't fall short are its driver-assistance features, which are not only abundant but also extremely good. The combination of adaptive cruise control with lane keeping makes the S550 Coupe nearly self-driving, as the car controls its speed and steering. However, it admonished me with a warning when I kept too light of a grip on the steering wheel at speeds above 20 mph. Below this speed, such as in stop-and-go traffic, you can take your hands off the wheel and the car will maintain its position in the lane, as long as its cameras can distinguish lane lines.

The surround view camera shows a top-down view of the car, along with a front or rear view, depending on which way you are moving. The imagery is very distinct and makes it easy to maneuver in parking garages or other tight parking areas without scraping against pillars or other cars.

I was really impressed with the S550 Coupe's automatic high-beams. Driving at night, the LED headlights switched to a high-beam setting on darker stretches of road, giving excellent illumination. For oncoming traffic, slower traffic ahead or areas with street lights, the headlights quickly changed to a low beam. The transition between settings was really cool, as the LED headlights changed the shape of their throw pattern rather than merely turning on and off a second set of lights, as in older cars.

2015 Mercedes-Benz S550 Coupe
The LCD instrument cluster shows how the adaptive cruise control system sees the world. Wayne Cunningham/CNET

These automatic high-beams rendered the car's night vision feature superfluous. Pushing the night vision button caused the virtual gauges on the instrument cluster to move off to the sides, making way for a black-and-white image of the road ahead, generated by infrared

. This feature is well-engineered, making it easy to glance down and see further than even the high beams project, which could be useful in rural areas where animals might be in the road.

Everything but the Internet

With the 2015 S550 Coupe, Mercedes-Benz gives its S-class sedan a sporty and high-class sibling. Like the sedan, the S550 Coupe shows that Mercedes-Benz has a lock on modern luxury, mixing high-tech elements with an extraordinarily comfortable ride. At the same time, the S550 Coupe shows exceptional power and confident handling. It's a car that does everything well.

That is, except for its connected car features. Somehow, Mercedes-Benz made a big misstep with the Internet connection in the S550 Coupe. And the issue doesn't seem to come down to bandwidth -- it seems that the data modem doesn't fire up when you start the car, connecting only when you attempt to use one of the car's built-in Internet features. This may vary in other markets, but in the US, these features are unusable.

Tech specs

Model 2015 Mercedes-Benz S550 Coupe
Powertrain Turbocharged direct injection 4.7-liter V-8 engine, seven-speed automatic transmission
EPA fuel economy 16 mpg city/24 mpg highway
Observed fuel economy 19.6 mpg
Navigation Standard with live traffic
Bluetooth phone support Standard
Digital audio sources Internet streaming, Bluetooth streaming, onboard hard drive, iOS integration, USB drive, HD radio, satellite radio
Audio system Burmester 1,540-watt 24-speaker system
Driver assistance Head-up display, night vision, surround-view camera, adaptive high-beams, collision warning, pedestrian detection, adaptive cruise control, blind-spot monitor, lane departure prevention
Base price $119,900
Price as tested $149,575

2015 Mercedes-Benz S550 Coupe

Score Breakdown

Performance 9Features 9Design 9Media 7


Available Engine GasBody style Coupe