Hmmm, this is interesting. I hit gravel, chunks of rock, sticks, cruddy pavement, etc. on my rides all the time. I've got about 1,800 miles on the Bontrager Selects that came on my Trek 1000. Should I be replacing these tires? They still look good to me, but I don't know anything! And I'd rather not have a blowout (knock on wood)!