In third generation form, BMW's X5 proved to be a luxury 4x4 that was bigger, safer, classier and came with a blend of performance and efficiency that some of its rivals could only wonder at. A 2WD option made the range a little more accessible and there were a whole series of dynamic suspension packages for those prioritising tarmac over tundra. The result was a car that, though no longer head and shoulders above the competition, could still set the standard most of them needed to aspire to. Let' check out this 'F15'-series model as a used buy.