honestly, it seems like its ALWAYS the rear rotor that lets go.

my car just had trouble starting and sure enough, 75psi on the rear rotor :[

 

yeah, all the engines ive seen and torn apart have been the rear rotor. i think i heard someone say that the S1-S4 have a tendencey to let go in the rear, whereas the S5 and up its usually the front. but i have no idea, ive never torn apart and S5, so thats just what ive heard.