The GL550 is larger than BMW’s X5 and Audi’s Q7, making it the better choice for those with several (or more than several) family members. The Mercedes-Benz GL550 is also a study in contradictions: It is a German-engineered, American-made, full-size sport-utility vehicle that drives like a car; its rear children’s seats provide enough legroom to accommodate adults comfortably; and box-like design belies its luxury interior. Mercedes builds the GL in the same Alabama factory as its M-Class midsize SUV, and the two share a number of attributes, including stiff chassis, leather- and wood-clad interiors, and rack-and-pinion steering. The obvious difference between the two vehicles is their size. The GL is considerably larger. But the GL also surpasses the M-Class with an optional but essential off-road package that adds two locking differentials, a two-speed transfer case, an adaptive air suspension, and 10.9 inches of ground clearance (up from the standard 7.9 inches). The GL550’s 5.5-liter V-8 develops 382 horsepower, which might sound modest among 400-hp Dodges and Jeeps, but the GL is something of a lightweight in this class—a lightweight that still can tow a three-horse trailer.