Yeah, if the rotors are thicker than 10.5mm you can keep them. You might as well replace them though, it stands to reason that if you don't, sometime during the life of your pads the rotors will wear thinner than the tolerance. I just did mine, and the job could not be an easier DIY. It couldn't be more simple, the difficulty comes in when you need to loosen some bolts that require a significant amount of elbow grease. I ordered my rotors online, they were only $50/piece. $500 sounds right for the stealer to do it, much cheaper as a DIY though. Have fun!