moxfyre

I'd say mine typically last 1500-3000 miles before I replace them, generally when about 1/4 to 1/3 of the pad is left.

Water probably isn't accelerating the wear, but dust and mud in the spray could well be. So you've put 320 miles on them, and they're already half worn? Ya, that DOES seem fast. It might be that the stock pads that came with the bike are really soft and wear faster. But I agree that they seem to be wearing out much faster than normal.

Personally, I like the Kool Stop Salmon-colored pads the best. They've had excellent lifetime for me.