Streetmaster to Airgap

You're opinion is unqualified on that subject.
You'd be better to know how to do it yourself before streaking the site and post bombing.

Looks like Modern Cylinder Head's opinion is unqualified too. Maybe they should come here and ask you what they should do on their CNC race program to improve the heads they currently do. If only everyone knew how much better you truly were they would beat a path to your door and Modern would go broke.