I have been in the hunt for the best heads for the buck and found that there are a bunch. It's true some magic can be done with so called lesser heads.
Allpro's seem to have the best flow, but as you said it is not all about flow numbers.
For your best bet I think, go with 18 degree heads, Self racing has a set of Clone oval port brodix that fully assembled go for $3500.00
intake flow at .700 is 420 cfm. pretty impressive. On a pretty stout 427 block they make over 930 hp.
I would say, well worth the money.