For starters, 7 bolts are at a disadvantage over 6 bolts by having bolts/studs that are 1mm smaller from the get go.

I think it was John Whalen who put half inch studs in his 2g with the compound setup, drilled and re-tapped the holes in the block larger as well to match the imperial size. Not sure where he got those from. He never had issues that I know of even with around 50+ psi of boost with that setup.