The PFC kit is fundamentally different in many ways from the StopTech/Rotora/Greddy/AP kits that I have seen.
PFC's two best defining qualities are their 2pc direct drive rotor which is very different from the way most rotors attach to the actual hat. The PFC rotor & hat fit together kind of like axle splines inside a tranny and that is how the torque is transfered. Instead of using the bolts to transfer the torque the actual body of the hat is the load patch. For any engineers out there they know that bolts don't always like being loaded in a shear load path. Secondly is their 1pc caliper. The caliper body is a 1 pc assembly that is much stiffer and lighter than having a 2pc caliper that is bolted together.
There is a detailed writeup on PFC's process and facility here:
http://www.motoiq.com/magazine_artic...g-systems.aspx