Miller- If you worry anymore your going to have to check into therapy. Just run the silver and black springs, silver on the aluminum and black on the carbon. Ive got three gallons out of a set of shoes. If your worrying about them being done before a main, or they do wear out in a day, something is definetly set up wrong. Ive been running the car for about 4 to 5 gallons and have got my 2nd clutch in it.