Keep it slow through the turns, build speed up before going up hills. Be -very- gentle with the throttle. I've driven a 740i (Pilot Sport tires) and an SL500 (Dunlop SP9000s) in the snow. The experience was fine... Provided I was very careful. Get the SP and don't worry about it. If you find you're unable to adequately modulate the throttle, then put a set of winter tires on. Nick