Best iron cyl head?

I think 360Duster is over killing the stroker point because it is only 372 cubes. It's like a seriously bored out 360. Though his mention of the RHS head is an excellent one. I thought RHS doesn't make that head anymore. Someone else picked it up I thought.

Mgunner's idea of a letter head is sound. The later 596/308 heads are pretty good too if you can not find a letter head. (X J O U) if the RHS head is not within the budget.