Mike By my reckoning a Super Rocket will have an alloy head fitted with hardened valve seats capable of dealing with lead free fuels. Can't say about the valve material, but even so I would agree that erosion after such a small mileage is unlikely.
So in the meantime it is a case of setting things up, and keeping a regular check on the clearances. As the motor settles you should find they will stay the same. If they continue to close up, it's a case of top off for a looky look.
Worst case scenario is a bit of top end reconstruction and re-assembly, if you are extremely unlucky, which I very much doubt. It will take a good few cycles of use for the gaskets to settle and as long as you can maintain the clearances, don't worry, just do a regular check.
We assume you set the cam in the same place each time, but having got it wrong a few times myself, I know takes a bit of skill to get it set up right.
Swarfy.