I can't speak for the MKIV but my MKIII is fine as long as I have a decent snow tire (all seasons don't cut it for me) and a set of healthy studded tires on the rear... but only if I go easy on the throttle. Hitting boost on hard packed snow or ice and I can spin them fast enough to throw studs out. As long as i take it easy my car is probably the most solid car I've ever owned in the winter. Although I can never wait to get the narrow snow tires off so I can stomp on it again.