The following review is for a 2013 Model Year. There may be minor changes to current model you are looking at.

Luxurious sedan with sleek coupe-like styling.

Introduction

Imitation may be the sincerest form of flattery, but for automotive designers it can also be a huge pain in the gluteal region. When your design is so cool that it provokes copies far and wide, what do you do for an encore?

The Mercedes CLS-Class is an excellent case in point. Introduced as a 2006 model, it was not only a show-stopper, it became the prototype of a whole new vehicle class: the oxymoronic four-door coupe. The term has created some confusion, with a number of unlikely four-door vehicles calling themselves coupes, but it appears to have lodged itself permanently in the automotive lexicon. 

Mercedes of course can use whatever term it likes, but to our eyes the CLS-Class is a sedan, with sleek lines that may seem coupe-like to some. And in its first extensive redesign, the smooth skin of the original has acquired more sculpting. The shape is familiar, there continue to be two models, CLS550 and CLS63 AMG, but the skin is a little edgier, and the look is a little more aggressive. 

The CLS-Class was created on E-Class mid-size sedan architecture, and that continues into this second generation, although all its dimensions have expanded slightly. This doesn't affect passenger capacity. As with the original, there's a permanent console between the rear seats, so the CLS-Class continues to be a four-seater. 

Introduced for 2012, this latest-generation CLS-Class uses turbocharged engines for increased power and improved fuel economy. The CLS550 comes with a 4.6-liter biturbo V8 rated at 402 horsepower and 443 pound-feet of torque. Fuel economy for the 2013 CLS550 is an EPA-estimated 17/25 mpg City/Highway, while the CLS550 4MATIC is rated 16/25 mpg. 

The CLS63 AMG version, from the Mercedes performance subsidiary in Afalterbach, Germany, is propelled by a 5.5-liter twin-turbo V8 rated at 518 horsepower and 516 pound-feet of torque. With all that horsepower, the CLS63 AMG still gets an EPA-rated 16/25 mpg. 

Both V8s are paired with 7-speed automatic transmissions, although the shift controls are different for each, as are internal gearing and final drive ratios. 

We found these cars feel heavy, but the pneumatic suspension handles the weight well, snubbing up and down body motions and keeping the car level during hard cornering. Ride quality is autobahn firm and the CLS550 inspires confidence in high speed corners, yet the air suspension irons the edge off gnarly pavement. 

The cabin is trimmed nicely, the sound system is orchestral, and it's quiet underway, save for the refined rumble of that twin-turbo V8, sotto voce, lowering the driver's inhibitions, tempting the driver's right foot. 

The CLS-Class was completely redesigned for the 2012 model year. The 2013 CLS-Class comes with the second generation of Mercedes's mbrace connectivity feature called, appropriately enough, mbrace2. Among other functions, mbrace2 provides access to internet browsing, Google Search, Facebook, Yelp, and news programming via the new MB Apps feature. 

Lineup

The 2013 Mercedes-Benz CLS-Class offers two engines: The CLS550 ($72,000) comes with a 402-hp 4.6-liter biturbo V8; the CLS550 4MATIC ($74,500) comes with the same engine but all-wheel drive. The CLS63 AMG ($95,900) features a 518-hp 5.5-liter biturbo V8. All come with a 7-speed automatic. (Prices are MSRP and do not include $905 destination charge.)

CLS550 comes standard with dual-zone digital automatic climate control, leather upholstery, 14-way power front seats, three-position memory, multicolor ambient lighting, COMAND system with 7-inch LCD, AM/FM/DVD/CD6, SiriusXM radio, traffic and weather, HD radio receiver, 10GB Music Register, Bluetooth, 80GB hard drive navigation with Zagat survey, harman/kardon Logic7 digital surround sound,

Premium leather upholstery is optional. Also optional: active multi-contour driver seat, heated and active ventilated front seats, split-folding rear seats, Keyless-Go, electronic trunk closer, power rear-window sunshade, iPod/MP3 interface, active LED headlights, rearview camera. 

Safety features standard on all CLS-Class: 12-way air bag protection, Neck-Pro active front head restraints, Attention Assist drowsiness monitor, Pre-Safe, Hill-Start Assist, Hold braking feature, tire pressure monitor, mbrace2, ABS, brake assist, electronic brake-force distribution, electronic stability control. Optional safety features include rearview camera, rear side-impact airbags, Distronic Plus adaptive cruise control, Blind Spot Assist, Lane Keeping Assist, Active Blind Spot Assist, Active Lane Keeping Assist, Night View Assist Plus with Pedestrian Detection, Parktronic with Parking Guidance, Active Curve Illumination, all-wheel drive. 

Walkaround

Launched as a 2012 model, this latest-generation CLS-Class is bigger than the original. At 113.2, inches, the wheelbase has stretched by almost an inch, and overall length, 194.5 inches, has grown 1.5 inches. Wide to start with (73.7 inches), it's even wider now (74.1), and the roof, 55.8 inches at its height, adds 1.1 inches. Front and rear track has expanded correspondingly. 

Those are all significant expansions, but the design team preserved the car's proportions, including the fast rear roofline that gives the CLS its coupe profile. Flared wheel arches and pronounced body side character creases give the second generation car a more muscular look, and LED headlamps light the way. 

Mercedes calls the headlamps an industry first, by virtue of two features: Active Curve Illumination, which varies the beam to provide optimal lighting on twisty night roads, and Active High Beam Assist, which functions as its name suggests to help avoid blinding other drivers. 

Interior

No Mercedes interior can be called Spartan, particularly at this price level, but this second generation CLS-Class represents an uptick on the elegance meter, with new materials, new trim, and the second generation of Mercedes mbrace connectivity feature called, appropriately enough, mbrace2. Among other functions, mbrace2 provides access to internet browsing, Google Search, Facebook, Yelp, and news programming via the new MB Apps feature. 

Most visible among the updated interior elements is the cabin trim, which replaces the previous matte finish wood with a choice of three materials: traditional Mercedes high gloss wood, piano black, or carbon fiber. 

Mercedes has gone to a column shifter, freeing space in the center console. However, the new setup offers only basic PRND gear selections, and paddle shifters are conspicuous by their absence. 

One other interior note: although the steep slope of the rear roofline still means that front seat passengers have more air over their hairdos than those in back, there's a little more rear headroom than in the first generation. 

Driving Impression

With its sleek skin, the Mercedes-Benz CLS-Class disguises its size, but this is a big car. And it's heavy. Although the 4MATIC all-wheel drive is one of the lightest in the business, curb weight of the CLS550 is north of two tons: 4265 pounds. 

The pneumatic suspension handles the weight remarkably well, snubbing up and down body motions and keeping the car level during hard cornering. The electro-hydraulic power rack and pinion steering is accurate, and nicely weighted, though some may find the level of effort a smidge high. And there's no shortage of grip. Even though the standard tires are all-season (as distinct from summer performance), the CLS550 inspires confidence in high speed corners, and is devoid of surprises. 

On the other hand, the CLS550 is no wraith, and in brisk driving on twisty back roads the driver is always conscious of the car's bulk. Quick changes in direction would be a lot quicker if it weighed about 500 pounds less. 

It would be quicker going straight ahead, too, but even so the CLS550 more than holds its own. The twin-turbo 4.7-liter V8 generates big-time torque (443 pound-feet) and it peaks just off idle, 1800 rpm, and stays peaked all the way to 4750 rpm. Throttle response is right now, not even a hint of turbo lag, and all that thrust, plus all-wheel drive, add up to very brisk acceleration, just over four seconds to 60 mph, and a quarter-mile in about 12 seconds flat. 

Mercedes lists top speed as 186 mph, whereupon a governor cuts in. We can neither confirm nor deny this claim, though based on our driving it seems wholly plausible. We can confirm, though, that at full throttle the V8 squashes occupants into their beautifully upholstered multi-adjustable seats with satisfying authority. 

We should add at this point that if your need for speed exceeds the robust capabilities of the CLS550, another $21,400 will put you in a CLS63 AMG, which brings 518 horsepower and 516 pound-feet of torque to the party (550 hp, 590 lb-ft with the optional performance pack). 

Whether the going is leisurely or in haste, the CLS is a very pleasant place to be as the miles accumulate. Ride quality is autobahn firm, but the air suspension irons the edge off gnarly pavement, the sound system is orchestral, and the cabin is otherwise quiet, save for the refined rumble of that twin-turbo V8, sotto voce, lowering the driver's inhibitions, tempting the driver's right foot. 

And when a quick stop is required, the brake system is more than equal to the task, providing sports car braking power and stopping distances. 

Fuel economy for the 2013 CLS550 is an EPA-estimated 17/25 mpg City/Highway, while the CLS550 4MATIC is rated 16/25 mpg. Impressively, the CLS63 AMG is rated 16/25 mpg. 

Summary

The Mercedes-Benz CLS-Class is no longer the only car calling itself a four-door coupe, and has inspired direct competition from Audi's A7. But the second generation continues to be a one of the slickest luxury four-doors going, as well as one of the most potent. Driven hard, the twin turbo V8 can be thirsty, but the CLS-Class escapes gas guzzler taxes, even in AMG tune. Whether you accept the four-door coupe business or not (as an aside, a wagon version has been added to the lineup in Europe; hard to think of THAT as a coupe), this is arguably the most stylish sedan in the Mercedes lineup, a powerful pleasure in everyday motoring, and still a head-turner wherever it goes. 

Tony Swan filed this NewCarTestDrive.com report after his test drive of the CLS550 near Detroit. 

Model Lineup

Mercedes-Benz CLS550 ($72,000), CLS550 4MATIC ($74,500); CLS63 AMG ($95,900). 

Assembled In

Sindelfingen, Germany. 

Options As Tested

Premium Package 1 ($4390) includes heated and ventilated seats; rearview camera; LED headlamps; adaptive high beam assist; KEYLESS-GO system; power trunk lid; power rear window sunshade; 19-inch aluminum alloy wheels ($500); split-folding rear seats ($440); rear spoiler ($400).