Let me clarify about the Burhead headers and a few other items in this thread.
Waylon [aka Burhead] and I had a deal where by I would finance production of "his" Buick headers and I would retain exclusive distribution rights. Long story short, he screwed me out of lots of $$$, so after this "battle", we parted ways.
I took the basic design [that was now mine] to TA where Mike and I, with his production guy, re-designed the headers. If you look closely, the off-shore copies are a cheap imitation of our laser-cut, finely fitted, expertly welded headers. We spent considerable time and $$$ to make sure they flow as good as possible. This part was NOT copied because it is more costly.
Sad part of this story, it will be a cold day in hell before Mike, or myself, [probably other vendors included] will invest our time, $$$ and experience in a product for someone to make a inferior copy.