Part minivan, part station wagon, part "what were they thinking?" the Mercedes-Benz R-Class is several cars rolled into one. Although the R-Class isn't quite as roomy as a minivan and only features six standard seats (a seventh seat is optional), it is essentially a luxury family hauler for those who would never consider owning a traditional minivan. Of course, the R-Class isn't as versatile as a real minivan. Its traditional hinged rear doors, for instance, aren't as family-friendly as a minivan's sliding doors., , Still, for those who can afford it, the R-Class is roomy, luxurious and available with two different engines, not to mention just about all of Benz's latest techno toys. It also comes standard with all-wheel drive for extra traction in inclement weather. For those wanting a versatile luxury vehicle that deftly sidesteps the perceived stigma of a minivan (or an SUV, for that matter), the Mercedes-Benz R-Class might make senseBoth trim levels of the Mercedes-Benz R-Class -- R350 and R350 Bluetec -- come with all-wheel drive and a seven-speed automatic transmission. A 2+2+2 seating arrangement (for a total capacity of six people) is also included for every model, with a 2+3+2 configuration optional., , The R350 is powered by a 3.5-liter 302-horsepower V6, while the R350 Bluetec gets a 3.0-liter turbodiesel V6. It's good for only 210 hp but delivers an impressive 400 pound-feet of torque along with highway fuel economy in the mid-20s. Both come standard with 19-inch wheels, rain-sensing wipers, dual-zone automatic climate control, a power driver seat, Bluetooth and an older version of Mercedes' COMAND control interface., , Upgrades include a panoramic sunroof, a power-adjustable tilt-and-telescoping steering wheel, a power liftgate, adaptive xenon HID headlights, a rear seat entertainment system, a navigation system and an iPod interface. Oddly, leather upholstery is not available on the R-Class -- Mercedes' admittedly nice MB-Tex premium vinyl is standard across the board., , In reviews, we've noted that while the R-Class is certainly roomy inside, with excellent interior materials practically everywhere you look and touch, its overall size can be a hassle in tight spaces. The rear doors provide a huge opening to ease getting in and out, but they are very long and can result in plenty of dings in the mall parking lot. Behind the wheel, the R-Class is a bit like driving your own personal high-speed train: It's big, it's heavy and it has an eerie way of making high speeds seem completely reasonable. Handling isn't an especially strong point, as the R-Class doesn't inspire much more confidence than a typical large luxury crossover. Neither engine will produce especially impressive acceleration.