How much snow would you say there was overall? Check out this ZJ on tracks up in Idaho
http://www.nagca.com/forum/showthread.php?t=42185
4ft+ in places.
American Track Truck makes some nice tracks that are much larger and have a total surface area of about 3,500sq/inches versus the 2400sq/inches of the Tatou tracks I have. If you had a heavier vehicle, and a lot of extra cash, the American Track Truck tracks would be the way to go.