I don't know either. I would also like to upgrade my brakes. But I remember reading a thread once which implied one were better than the other. I believe it was something along the lines of the slotted being cast and drilled rotors being drilled, not cast?? But what about pads? Which pads are the best or what is the best combo? Mostly on road here, only other use is slow rock crawling. What about the ebc? green or yellow pads that I see in quadratech?