http://www.porterfield-brakes.com/
David,
Sounds like our cars get a similar amount of use - 3K per years. Pads have been on the car for about 5 months and seen two open track sessions. They still have plenty of meat on them. I scientifically proved they work better: I measured the temperature of the of the rotors with an infrared temp gun. Porterfields were running about 100 degrees hotter (325 vs 225) and thus functioning better as a heat sinc (sp?) Porterfield says these are perfect pads for rear of a street/track car. They are agressive, but have not hurt the rotors.