Hands down one of the classiest cars on the market, both the two- and four-door configurations of the BMW 6 Series will turn heads. If you're so inclined, this elegant car is available as a convertible. The least powerful engine generates 315 horsepower, which isn’t too shabby at all. At the other end of the spectrum, the M6 offers the Bavarian brand’s most powerful engine (600 horsepower).