Carbotechs. Most of the Z guys I know are using those, at least those racing around the VIR/CMP/RRR area. 10s seem to work well, I have used 12s and like those, and Parrish was going to try a set of 8s and let me know how those go.

12 > 10 > 8 with respect to brake torque. No ill effects on rotors with the 12s, even at CMP. I'm sure there are other pads that will work well too. I've been using Carbotechs for about four years and enjoy their service as well as the product.