The twin-kidney grille, quad headlamps and other classic cues readily identify the 6 Series cars as BMWs. The M6 versions get a uniquely styled, more strongly sculpted front fascia. The 6 Series shares some key elements with BMW's 5 Series sedan, but the 6 was designed from the ground up as a coupe, and subsequently as a convertible, rather than a sedan with two doors welded shut or a coupe with the top chopped off.

This is a classic BMW 6 Series: The front and rear overhangs (the distance from the wheels to the bumper) are short. The cabin separates the long hood from the short deck. The 6 Series cars are shorter than the 5 Series sedans, but they benefit from a relatively long wheelbase (the distance between the front and rear wheels). In sum, you suspect these cars handle great just by looking at them.

The primary turn signals are located above squinty-eyed, compound headlamps, which wrap well around the corners to the sides of the car. The grilles take front and center stage with no bumper ledge in front of them. When viewed from overhead, the front corners look rounded, giving the 6 Series a shark-like nose.

In profile, the lines are sculpted but clean. Sleek, Euro-style combination side lights-cum-turn signals in a thin slit at the trailing edge of the front wheel wells give the impression of attention to detail and on the M's discreetly house the unique, stylized logo distinguishing those from the 650s. The 6 looks raciest in front three-quarter view, which happens to be our favorite angle on the car.

From the rear, however, the 6 Series cannot be identified as readily. The tail lamps and badge label it as a BMW, but the back end looks different from past BMWs. The tail lamps wrap around to the sides, so there's no precise break where the rear of the car ends and the side begins. As with the new 7 Series sedans, some critics don't like the way the rear deck looks somewhat disconnected from and perched atop the rear fenders. BMW points out that the high deck improves downforce, and therefore rear grip, at high speeds and allows for a big trunk.

In any case, this is a tidy, attractive car that looks sporty. It's best in silver and other lighter colors; the design details tend to blend together on darker cars.

There are also some interesting design features that aren't apparent to the eye, starting with extensive use of weight-saving materials. From the windshield forward, the 6 Series' load bearing structure is made of aluminum, just like a commercial airliner's. Its doors and hood are also aluminum; the front fenders and trunk lid are composite materials. A carbon fiber roof on the M6 Coupe reduces weight without compromising safety. At the same time, because it's the roof that's lighter, the effect is to lower the car's center of gravity. The underbody is shrouded in more high-tech plastic, much like the wind tunnel-groomed bottoms of F1 race cars, to improve aerodynamic efficiency.

The soft top looks great, featuring a fastback roofline with fins on the trailing edges that frame the vertical rear glass, much like vintage Ferrari coupes, giving the convertible the same side profile as the coupe. The rear glass can be raised or lowered like a side window by pressing a button. Replacing a metal roof with a convertible top often times tends to reduce structural rigidity, so BMW has reinforced the B-pillars and the lower sides of the frame, and built the windshield with an extra-high strength frame. This not only improves rigidity, but also adds an extra element of safety in the unlikely event of a rollover.

The 6 Series' standard adaptive headlamps pivot to aim toward the inside of a corner as the steering wheel is turned. This helps throw light around a bend, reducing shadows and improving visibility for the driver. Sometimes just that extra moment of warning can make for a safer and more enjoyable drive. The 6 Series also features BMW's adaptive LED brake lights, which illuminate more intensely in a panic stop. BMW contends this conveys the gravity of the situation to drivers following when you slam on the brakes, but it presumes those following know enough to understand the brighter brake lights' warning message.