With all that's offered on the X5 3.0si, there would seem to be little reason to consider the 4.8i model, especially considering its $55,195 base price. That's true, until you consider the 4.8i's 350-horsepower V8 and additional standard features such as a rear automatic air suspension, premium leather seats, walnut interior accents, and larger brakes. Options generally mirror those of the 3.0si, with the exception of no-cost poplar or bamboo wood trim (swapping out the standard walnut) and optional 20-inch alloy wheels.