The iron vs aluminum cylinder head argument is over.

I think a lot of the valve issues were from the old two piece valve days. I’m sure Edelbrock probably doesn’t produce their valves. Most of these heads like 440source (stealth), Speedmaster etc, have been around for years. With the internet today if there was a problem we would hear about it daily. Now I and others have seen lots of tight valves guides that will bite you on the butt but I’ve seen that with high dollar heads too.