While a followup from another member responding to my post spoke of the redneck engine builders, my post did indeed advise the guy to take his heads to a marine guy rather than the local speed shop.
This had nothing to do with the "redneck-ness" or unreliability of car speed shops, but more to do with the different requirements of a performance marine application versus a drag car application.
Marine motors spend FAR MORE time at high output levels than drag motors. While a drag head guy may wield a "mean" die grinder and get awesome flow numbers off his flow bench, his heads need only to produce max output for 10 seconds at a time.
Obscure things such as valve seat width, oil flow around the valvesprings, thickness of the edge fillet on the exhaust valve, mating surface of the rocker stud to the spotface on the head casting - these are all "little things" that a hometown drag builder may not pay any attention to. Those things won't make a drag motor go any faster or last for more passes (in fact, the desired valve seat width for a blown marine motor is far thicker than you'd want for best flow on a set of drag heads.
Marine motors are BASED on car motors. Good hi performance marine motors, though, need to have several areas addressed for best service in their environment that differ from cars. And most of it has to do with cooling, lubrication, mechanical fatigue, and thermal growth...
Sorry if anybody took offense.