I have ridden thousands of miles with the cassette and the wear has been neglible. I figure the 11 tooth sprocket will go first since I use it a lot but it hasnt happened yet. I do use waxed chains and rarely ride on wet and muddy road so that maybe helping. BikeGang gave me the sprocket as a tester BTW. Mighty nice of them. It would be nice to replace the one piece cassette with a different one which had removeable sprockets and use an 18 tooth for the low.