Hey Phil, everything on my bikes is 'homemade' so to speak. I know of the problems with Ti, but have no experience with it myself. Give me a pm about the prizes etc.
What I meant in my comments about the head of the F2, is that in day to day practice it's crap, mainly because of it's habbit to eat valve guides ie oil consumption. In theory it's a better design, it just doesn't show it. You're engine man may have a point about the exhaust valves, to big means loss of (air-)speed. Am very interested in the outcome of his investication. It really good to have someone like that 'around the corner'.
Rob