Joe you made much sense and I couldn't agree more. I think with the rollers reducing the side loading on the valve stems, thereby reducing friction and perhaps heat is enough of a reason. That said with the higher lift cams they can certainly be put to good use. As far as any HP goes I would say there are very little gains provided the geometry is correct in both applications. I'll let you guys know this week on a 540.
I do know one thing for sure and that is I wish I was the one who invented them. Was that - Harland Sharp???