The contrasts that exist on the 4.8i, and do not on the M model, make the 4.8i visually more interesting. Aluminum & black running boards, black bumpers, black rubbing strips, black wheel well trim, dark roof rails, etc. all add to a more visually distinct look that the all-one-color X5 M just doesn't have. I still think the 4.8i and even the sport model looks better then the M.