What's new for 2007: The R63 AMG stands out for its more athletic appearance. Its 20-inch rims are the most obvious indicator, but the R63 also sports aggressive front and rear aprons, a unique grille and deeply sculpted AMG side skirts. The new R320 looks identical to the R350, except for small CDI badges that indicate its diesel engine.

The Mercedes-Benz R-Class is a big machine. It's 14 inches longer than Mercedes' M-Class sport-utility vehicles and longer than the full-size Cadillac Escalade SUV, but lower to the ground than both, making it easier to step inside. The rear side doors are very, very long. That makes getting into and out of the second- and third-row seats easier, but it can cause problems in tight parking areas. With curb weight for the V8 exceeding 4900 pounds, the R-Class is heavier than some full-size SUVs.

Expansive size pays dividends in abundant space inside the R-Class, as fully 65 percent of its volume is interior space. The typical sedan has a much lower ratio. Mercedes stylists have also done a good job disguising the R-Class's functional intent with a swoopy, appealing design.

In many respects the R-Class is striking, and handsome. Its hood rises sharply into a large, steeply angled windshield, and sweeping front-to-rear lines tend to minimize its bulk and create some visual excitement. Sculpted front fenders flow back from multi-element headlamps, and an aggressive grille adds character. The bodywork also makes the R-Class a fairly slippery vehicle. Its 0.31 drag coefficient is lower than some sedans, and that helps minimize interior noise as air streams over the body surfaces.

Four wheel packages are available, ranging from 17 to 20 inches in diameter, intended to add either a touch of elegance or a bit or racy style.