awesome clutch ! have had two of them and recomend over stm any day...go for a 5 spring if you can..makes lever very easy..two finger operation..have 8k on current with surflex plates and beat the hell at off her at the track 12-15 x a year and still going strong! sorry pict was taking after crash!
The Ducabike, STM, Maduc, Bucci, DP performance, etc.etc. all make a ball/ramp style slippers, its proven & works well, in fact most parts are interchangable between the companies. (I don't who copied who first, I believe Bucci was the first to make it)
The slight downside is that the clutch plates wear down faster, & the clutch does require maintenance. (Cleaning & regreasing) Aloha Alex