BMW's American-built SUV came in three models in the 2006 model year: the 3.0i with a 225 horsepower, 6-cylinder engine, the 4.4i with a 315 horsepower V8, and the 4.8is with a 355 horsepower V8. X5s have all-wheel drive without low-range gearing, and front side airbags and front and rear head-protecting tubular side airbags come standard. Compared with previous versions of the X5, the 2006 models took critical hits, with professional test drivers complaining the car wasn't all that practical. "BMW knows that most luxury SUV buyers spend about as much time off-roading as they do in the 99-cent store," wrote one, adding that while the vehicle drives nicely and can carry five passengers comfortably, "it wouldn't be a good choice for home improvement projects or any other activity that requires serious cargo capacity."