the braking performance is NOT depends on how many piston a caliper has! also, the stock BMW brakes, even tho isn't the best, but they are not bad at all!! just give it a good set of race pads, and you will be fine!! don't believe me? see a pic that a track side photographer took a couple years ago for me. pay attention to the front disc!! it's 100% non photoshop'ed btw!!
I was just running euro rotor w/ a set of Hawks HT-10, and all day long I have no problem w/ the brakes at the track!
well, I must confessed at the end, I did eventually swap to a set of brembos tho. but main reason is b/c I got it at a very good price!
