I had a conversation with my local "real auto parts" (builds high hp racing engines) shop discussing the stainless steel aspect. He said that the older gassers used stainless in manifolds, headers, etc and had a real problems with physical growth of the stainless as it went from cold to hot. Sometimes it would grow over 1/2" and screw up all the mounting system. Did not seem to matter what # stainless it was.
Obviously that had to be taken into the design characteristics with stainless, but I would really like to hear how it is doing after a year or so.
True, cast takes on the heat, but cast has been around for quite a while. Just an interesting idea from a pretty knowledgable gasser.
Bob Weis