to many things go into this to be able to give a correct answer, your better off doing a search on TM8's.
if you want a mile number than you need to state boost levels, fuel used, oil used, what kinda of riding, mountain or trail use, how much maintance is done all sorts of stuff goes into making a boosted motor last.
if everything is done rite you can get thousands of miles out of one. Screw up a couple things and it's game over.
