Take this with a grain of salt, but keep in mind that Porsche put out a TSB indicating that only their OEM bolts should be used because they have those floating washer thingies on them that help retain the proper torque specs over time, and that using aftermarket wheel bolts without those "spherical collars" can result in bolts loosening after the driving the car, even if they were tightened to the proper specs. Apparently, they say that those collars were specially designed in an alloy that matches the wheel material. Whateva.
Also, there is a TSB that states in 2004, Porsche shortened the OEM bolt height by 2mm (the bolt head, not the thread), in an effort to further reduce unsprung weight. I just purchased a set to use when I put my summer wheels/tires back on. Should add at least 5hp!
