Yep, my machinist measured them and the heads maxed out at .510. .526 will definitly cause killed seals. I just checked and intense still advertises it as stock head safe.
But speaking of, I love my machinist (in a business way, haha). Got him the pass head tuesday to look at the valve to make sure it was still straight. He saw the seals were beat up all across and wanted to see the drivers head. Got it to him wednesday after work, springs showed up Thursday and got them to him after work. Dropped the valve seals off today after work and he was working on them. Said they will be ready Saturday morning. 3 day turnaround with all his other projects he has laying around and being one guy, couldnt be happier. Ill probably only get like a $100 bill for a complete disasemble, knock the seal down and re assemble.
Heads should go on sunday. Just waiting on my blower gasket and I need to run to the gm dealer and get more blower oil since my rotors have to get swapped. All the teflon flaked off the rotors.