The first Mercedes-Benz CLS was a segment-defining car when it debuted in 2004, stamping the "four-door coupe" term into the automotive lexicon whether people liked it or not. Unlike anything else before it, it was a modern car that changed the course of automotive design. In the years since, scores of similarly rakish four-doors have emerged, with even mainstream cars like the Honda Accord boasting "coupelike" rooflines. This latest, third-generation CLS is prettier than the previous model, but it's also less distinctive than the rest of the Mercedes lineup and lacks the styling verve that the original car had.

The AMG's rear-biased all-wheel-drive system provides sure-footed traction while allowing for some playfulness, especially with the stability control in its Sport mode, and the staggered Pirellis never make a peep under hard cornering. The electrically assisted steering is direct without being overly quick and passes along a surprising amount of feel and feedback. But the CLS53 also feels let down by its chassis, which can get unduly unsettled around off-camber corners or over rougher pavement. Even with the adaptive air springs in their softest Comfort setting, ride quality is brittle and choppier than we'd prefer in an otherwise luxurious sport sedan. The CLS's structure simply doesn't feel as if it has the vaultlike solidity of the E-class's chassis; even the smallest bumps are felt and heard as shudders throughout the interior.