I purchased these tires for the winter of 2008. I have used them every year since then, including this 2011 winter season. My Prius now has 63000 miles on it so I guestimated about 30k have been on these tires. The tread is maybe half worn if that. They are great in the snow, ice, and rain. Last winter we had a storm that dumped over a foot of snow while I was at work and the only problem I had getting home was seeing out the windshield because I was actually plowing snow with the bumper. They are loud. but I got them with the studs so I was expecting that. Would buy again for sure.