Unfortunately the fast guy's are having some problems. Fortunately, it appears the factories are footing the parts bill. Gearbox, clutch, valve springs, and cooling issues, will all pushed to thier limit if rode by a pro. I don't see the need for concern by the average guy or even racer. The valve spring issue would be my biggest concern, and can be remidied with a set of quality valve springs. From what I know, Kibblewhite will be releasing a set of replacements shortly. When a valve drops it's $2300 at the dealer level.