I think as with any head cam profile comes into play. And just like any serious builder many cams are tested. All of a sudden one outshines the others.
BPE heads are not W7 or better. But, for a ported casting pretty good. Extra money for intake and rockers is necessary for his relocated intake valve heads.
I chose a basic replacement aluminum head very similar bit, unported for my sons cars. They are grunt engines to cruise.
If they were to cam, intake, and carb up. I would definately call Rod.
Not many are keeping up the LA engine parts. Don't be so eager to talk the guy trying down.