I'm glad this thread has generated so many responses. It has helped me make the decision to go with a quiet version of the cam gears. The idea of a chain stretching and ultimately breaking, (Not to mention the effects of imprecise timing), I'll take the quiet Pete Jackson set-up. The longevity and reliability is worth the price. Everyone has a different vision for their Zcar, but it's great to have the access to the minds who love the car and want to not only keep it alive, but make it better!