I recently put on new rotors and 100 pads. The pads needed some sanding to fit, about 10 min total with an orbital sander. A small amount of grinding is needed to make them match perfectly with the rotor (Dan can explain in detail). I do notice significantly better stopping power than prior to the service. They're supposed to wear slower than the 80 pads, which is good as many report 10k on the 80 pads.