Ask BadSport. No....I take that back. Don't ask BadSport, because he is just as e'ffin sick as I am of telling people that a set of 150 buck headers FIT and WORK.
I have had Summit headers and IIRC, it was Hedman headers fit excellent, zero issues. Hooker, Black Jack, Cyclone, and a few others that didn't fit but worked great on my buddies identical car.
Quality control sucks at most of the big places I think. Perhaps, this S/S header guy actually takes the time to make sure it is bent and welded right? Perhaps, perhaps not.