3 cross country rides and a lot of miles in between on Bontrager race liotes with kevlar and never a flat. I don't plan to change tire brands anytime soon. 3 sets of tires in 40,000 miles over 5 years is enough proof for me. Nor were they entirely worn out, I just routinely put a new set of tires on before a cross country ride. I also check my tires after every ride for nicks cuts and stuff stuck into them. I am a great believer in the "an ounce of prevention= a pound of cure" approach.