Originally Posted by footie
I don't want to say something out of place here, just in case you happen to drive a 335ix but I will tell you this, when you start to compare the x-drive to quattro there isn't any comparison.
Quattro has an uncanny nack at finding grip where there is none, the brother drives an X5 and where his car starts to spin the wheels due to very slippery conditions my S5 has no problems at all.
I am sure many here will disagree with this and show numerous evidence for it, I can only say what I personally have experienced.
Agree... and most USA magazines as well have stated so: Quattro >> xDrive.