I know they "claim" they aren't supposed to be harmful to rotors, but I came across a website with over 50 reviews that these EBC Green Stuff pads are not what they claim to be.....almost all of these people have warped rotors and no problems with other types of pads. All cases have large amounts of brake dust and over half have brake sqealing all the time. I know some people have and like these pads, but the majority rules on this one. I don't think these are totally organic pads either....even if they do claim that.