Originally Posted by Will@PRS
Unfortunately I was not able to drive the 135i with the ACT, but I have driven an HPF clutch on a 335i and thought it was horrible. The SPEC clutches are great with the E60 M5's they we have worked with, but every car is different.
If you want to try out the ACT clutch you are welcome to come by the shop next TIME our 135i customer comes in with it and I'm sure he won't mind you trying it. He will be back soon for M3 suspension upgrades.
Thanks for the info, I am still on the fence. At least for now, are you Will that is friends with Jack Adams from Fields in Daytona? He told me about you and your shop.