Maybe... all of these heads (Speedmaster, ProMaxx, Airwolf, etc.) could all be manufactured at the same factory or factories in China. The head companies just place orders and have their name put on a box, or etched into the end of the head.
Same for the big block casting out there. I bought some PC vectors after speaking with Jeff at MCH. He advised that the castings were decent but to buy them bare and build them using good valves, springs, etc.
