I am considering buying a slipper clutch and came across the Italian made STM , which claims its slipper clutch is being used by Chad Reed, David Vuilelmin, Michel Pichon, Bartolini, Chiodi, and Stefan Merriman, so quite a reputation. I wondered if anyone could help me make decision. What I noticed is that the STM has no external regulation, one has to buy a different coil for different adjustments. But STM seems very keen on the Yamaha 450, any suggestion? Who?