This new head will be aluminum. Several reasons why the hybrid head isn't more popular is most racers have no interest in it, plus you don't end up with any better of a head than if you built a true brazed lump port head or a Kirby 12 port head. Also, you weaken the block too much by changing the bolt pattern to the head by redrilling into sections that don't have bolt bosses cast into the blocks deck surface. The later LS style V8 head would probably be a better choice because it comes much closer to using the existing bolt holes in the block than the early V8 heads do. Its also easier to make the head fit the block instead of trying to make the block fit the head. By the time your done, you just have too much money spent on doing a hybrid head compared to buying a head that already fits the block that doesn't require altering the block or head. I think the hybrid head was more of a "because he could" kinda' thing instead and just being different than thinking it actually was providing any real gains over other options that are available, and I think others see it as that and haven't tried to do it for themselves.
