Here are two paragraphs from http://www.stoptech.com/whitepapers/warped_rotors_myth.htm

"There is no such thing as pure abrasive or pure adherent friction in braking. With many contemporary pad formulas, the pad material must be abrasive enough to keep the disc surface smooth and clean. As the material can cross the interface, the layer on the disc is constantly renewed and kept uniform - again until the temperature limit of the pad has been exceeded or if the pad and the disc have not been bedded-in completely or properly. In the latter case, if a uniform layer of pad material transferred onto the disc face has not been established during bedding or break-in, spot or uncontrolled transfer of the material can occur when operating at high temperatures. The organic and semi-metallic pads of the past were more abrasive than adherent and were severely temperature limited. All of the current generation of "metallic carbon", racing pads utilize mainly adherent technology as do many of the high end street car pads and they are temperature stable over a much higher range. Unfortunately, there is no free lunch and the ultra high temperature pads racing are ineffective at the low temperatures typically experienced in street use.

"Therefore - there is no such thing as an ideal "all around" brake pad. The friction material that is quiet and functions well at relatively low temperatures around town will not stop the car that is driven hard. If you attempt to drive many cars hard with the OEM pads, you will experience fluid boiling, pad fade and friction material transfer - end of discussion. The true racing pad, used under normal conditions will be noisy and will not work well at low temperatures around town. "
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David (98 S70 T5SE Black, misc mods (mostly lighting), red calipers) (92 940GLE)