I had a service visit this week and asked what a rotation would cost since I was there. He said $75. I said that was a bit steep but for the sake of convenience gave the go ahead. The guy then got down and began inspecting. After a thorough look at all four he announced that I needn't worry about a rotation now and possibly never. His opinion after a year of observation, is that the P and AWD M3s wear these hard 45psi tires extremely evenly. His take, if the rotation is free, do it. If not skip it. This advice does not apply to the RWD models.