I don't mean how long in time, but how much damage do you tolerate before you toss them? I used to chew up my sticks on the side of the hi-hat, but I've gotten over that in recent years. Now the thing that happens is the bead wears down, or a chunk flies off leaving a flat spot. I had one set I used for a long time and I suddenly realized my ride sounded terrible because the bead was badly eroded away. I'm working on speeding up my doubles too, and a crappy bead with flat spots doesn't help. I recently swapped out my sticks and a big chunk of the bead came off within a week. Is this just the cost of doing business?