lol, thats detonation that caused that. Not imperfections in the surface. An oem gasket is not very forgiving to any detonation and will break easily and blow.
Cosworth headgasket is a very nice affordable gasket. Very well designed and ive yet to have any problems at all with mine. 34psi of boost. It withstood some detonation during the tuning process and never broke or gave out. They are 157.00 from FRsport.com. 1.1mm 87mm bore is the one i usually get. Great gasket for any type of build. Big, small, whatever.