Besides the familiar sedan and wagon, the line-up includes an E-Class Coupe and Cabriolet (or convertible), which replace cars that had been known as the CLK since the mid-1990s.   All E-Class models share the same underpinnings, and nearly identical exterior dimensions.  

Styling for all E-Class variants is quite similar, too, at least from the windshield forward.   Every design cue, panel, lamp and piece of glass was changed for 2010.   And although they tend to look bigger than their predecessors, more like Mercedes' premium S-Class, they really aren't.   The new E-Class variants share a larger grille, and a new trapezoidal headlamp array with multiple elements and square corners instead of the traditional E-Class oval lamps.  

From the windshield back, the new E-Class models differ, of course.   The two-door Coupe's roof flows more evenly than the sedans, with a less prominent notch where the rear glass tapers downward.   Yet all variants share a set of four lines rising from front to rear in or on the body.   Rear lamps are similar on Coupe and sedan, as are the rectangular exhaust tips built into the bumpers, rather than hung below them.  

Mercedes designers took great pains managing airflow through, under and around the E-Class, producing a sedan with a drag coefficient of only 0.25, despite its big, brawny appearance.   That makes the E-Class the most aerodynamically efficient four-door car in the world, according to Mercedes.   The company claims that the Coupe's Cd of just 0.24 is the best overall figure for any series-production car anywhere.   Other things equal, a lower coefficient of drag means less interior noise and better fuel mileage.  

The E-Class wagon is offered in Sport trim.   That means a bolder three-bar grille, more aggressively flared rocker panels and perforated front brake discs with painted calipers, visible through five-spoke 17-inch wheels.   The wagon's roof creates a dramatic teardrop shape in profile, with LED taillights that wrap around the rear corners of the car.  

The E-Class Cabriolet comes closest in appearance to the Coupe.   The lower half of the body of the E550 Cabriolet is designed by AMG, Mercedes' partner in high performance, and its sleek edginess reflects that attitude.   The power convertible soft top is one inch thick, and performs like a hard top, so well insulated that it actually dampens sound more effectively than the steel roof on the coupe, according to Mercedes.   It lowers and rises in 17 seconds.  

The lines of the soft top are not as sleek as the lower half of the car.   The rear glass is not expansive, so it could fit in the trunk without taking up too much space.   This means more area of fabric around the window, making it look thickish back there, losing some of the beauty of the Coupe.   And for all its edges in the sheetmetal toward the front of the car, it has fairly round hips, especially noticeable in the Cabriolet.