The X5 does just fine off road with the right tires and the right driver.
Seems all of the videos I've seen it getting stuck involve idiot drivers with on-road tires in situations a lot of dedicated off-roaders would have difficulty in.
Not to mention auto mags testing it off-road with on-road tires and giving it bad ratings because of it.
I bet most people would say that GTOs aren't any good off-road either but witht he right driver and the right line anything is possible: