I'm not sure why you're calling them "low cost". They were 98.00 less than Edelbrock heads when I was shopping. I also know at least two people who bought them had to have a valve job done on them because of seat run-out. I'm not trying to be disagreeable, just stating observation.
I think when I do the other engine being I'm fighting the scuzzy radiator syndrome with the leaking oil gallery rocker feed lead I'll use Jay's heads providing they work with a factory intake and are available.