I'm currently in the market for purchasing Granatelli's drilled and dimpled zinc coated rotors. I noticed that you purchased a set and I was wondering have you had any bad luck with the dimples and slots having any type of rust problems. I know after a wash the parts of the rotor where the brake pads touch will eventually knock off the rust but my main concern was with the dimples, slots and outside of the rotors. Any input would help thanks!!