I think that if you can find a mechanic/engine builder than you can work with and throw ideas around, it shows intelligence on their behalf if they can suggest alternate parts to what you request AND explain why you need them, but they have to be happy if you dont want the extra expense involved etc.
Eg My machinist/engine builder told me that I will really need to run roller rockers on my Cleveland heads, but was happy enough when I said the cost of the machine work required isnt really worth it when for not much $$$ I could buy a set of aftermarket heads already set up to run 7/16" studs for the rollers, Same again with getting real stuck into the ports.
I have found GOOD "engine builders" much easier to work with the the local performance workshop, because and Engine builder does one thing, Builds engines.
So he isnt a jack of all trades, master of none.
I had an engine built by a "performance workshop" In melbourne, and I rekon blind freddy could have done a better job.