My brother drove with emergency brake on and the dealers told me my rear rotors are warped. so i need them. and was wondering whats a good replacement, I don't drive that aggressive. Can i shave my current rotors?

what do you guys thing about this kit:
http://www.cvrmotorsports.com/store/...roduct_id=1514

and does it matter if it is cryo treated or not? i have an 06 g35 mt with 40,000 miles