8.5 lbs? wow jess, that little baby is going to be a handful on the street... you'll have to drive it like you stole it
It seemed to help the 4bangar a LITTLE bit with my LTW flywheel, but probably just on the ass-dyno. Did feel like a little lose of low-end on the uphills though... but it definitly felt abit quicker.
FWIW, Fidanza makes a 13lbs one for M3 clutch, which is what I have... I believe Ireland Engineering makes one thats around 8lbs... UUC makes a couple different ones too.... I think the 13 is a nice balance.
Probably not worth it though unless you go for the M3 clutch, imho.