my dad and me both have grizzlys he has mudlites and i have swamplites, we do a crap load of winter quading.i would have to say by far swamplites kick mudlite ass
the best kinda tire you can get for snow is a tire that would say have a simal tread pattern as a tractor tire, mud buggs and outlaws do extreamly well in the snow from my personal experiance, outlaws are by far the best in anysize.... but mudbuggs do verry well also. I find that the mud lites have issuse climbing up hills in snow wear i'v had no issues in way more snow with the buggs or outlaws.
If you have money get tracks. There awsome... Mud, Snow, Pullin anything, Pushin. But if your lookin for tires I have Mud Lites and they work great in snow as well...
i was just looking in the dirtwheels magazine and i see ITP has some new tires out. they are mostly baja and hard pack tires but they also have one called "tundra cross" made specifically for ice, snow and frozen soil. they come pre-studded but only in 25 inch. i run the maxxis zillas in the snow, as long as you have plenty of power, they go quite good.