I would like to share with you my experience with Kevlar clutch from Hi Tech Exotic. the car shift much faster between 7K and 8K RPM I would say %30 faster. in fact I race two R8 V8 like my car and I am a head each time I shift gear half a car.
the Hi Tech Exotic claim that the clutch will last %300 more than stock one. I am happy with it.
check out this video for speed test I did and watch the RPM
the guy I dealet with name is Sean this his email: