First off-please turn off the caps.That is interpreted as yelling.Edelbrock does build a good product.But to make a blanket statement like that isn't accurate.How did your street engine builder come to that conclusion??.Does he have the equipment,flow bench,test for for what he is saying??.Hell RHS builds one waling aluminum head as so many other companies do.Bottom line I have my doubts the ONLY Edelbrock check out.Seems some limited experience is coming into play.Short of tie-ing in Edelbrock's $3,500 EFI system with the heads my ref to them as been a mid moderate kind of mod.