Did you run the engine yet???
Do you have the cnc'd version or the as cast version???
I have 2 sets in my shop right now and they are both for sale...I ran them across the flow bench and they were sick. I think out of the box they went like 190cfm @.500 lift...With out getting into a bunch of cylinder head tech they are just a real bad design to make power...
I have herd from some other shops that there might be some issues with loose guides and seats,,,But it's just a rumor right now and i have not been able to confirm it..
If you want a cheep set of aluminum heads just to run on a beater or pick-up truck they are ok... if you really want a fast engine there not worth the work..