I personally wouldn't do more than a bowl-blend and general light port cleanup on a set of stock iron heads. I didn't even ask to have my heads ported, Bret Bowers at Atlas Performance felt compelled to open them up because he said they were terrible in as-cast form; also the owner Jason Gonzalez is a really solid guy and I think he wanted to do me a favor. I worked at that shop for about a month and couldn't cut it so I think he felt a little bad about that, also I tried bringing in engine parts for machine work multiple times over the past few months and they kept taking too long where I ended up just taking the parts back and going a different route. The porting job I got was worth $1500 in labor btw, not trying to show off just putting in perspective how much work a good porting job is. I'm truly lucky to have gotten that and will always recommend Atlas to anyone I meet locally needing performance engine work.