I gotta chime in here, If I had a bike with only 30K miles on it and it died I'd be looking at where I failed in general maintenance. I'd also be pissed off, really pissed off.
Modern sportbikes are able to go over 200K miles with proper maintenance.
You also make a comment that it's had "hard" miles you give an example of "track days", sportbikes are BUILT FOR track days. That is not hard miles. They are made to rev out and brake hard and do it for a LONG time, WITH PROPER MAINTENANCE.
Sounds like you need to learn how to properly maintain your ride.
30k on a track bike is a lot. Consider a privateer club race bike is typically good for about 3 seasons before catastrophic failure. This is for any brand. Also modern 600s and some liters bikes are extremely high strung. The 675 is rated at 126HP. That's 186.7HP per liter. The only liter bike rated at that sort of power is the S1000RR and do you know what sort of engine life they are getting out of it? Less then 100k. Yes you can get lower power sport bikes that will last 200k like the FZ1 and most of the Japanese liters bikes rated for under 160hp but if you want cutting edge HP/CC then your going to pay for it with shorter engine life.
Just out of curiosity mac, if the valve head did drop off what kind of work would he be looking at for a repair?
It can vary a lot. In the best case but very unlikely just a valve. Normally however you would be looking at minimum all the valves on that cylinder. Worst case, piston, cylinder, valves, cam, head. The worst case is what our race bike needed after dropping a valve at the end of the straight at PIR.