OBX are knockoffs of the PaceSetters, but better material (304ss vs mild). SSAC/XS Power stainless headers are knockoffs of the more expensive SLP's, also with better material than the originals (321ss vs 409ss).
I don't know about fit on the OBX, as nobody's mentioned getting some yet (I'm sure they'll be selling, though). The SSAC's have had very little fit issues, and if you properly clear a path behind the engine, install is not an issue. I've installed multiple sets from the top-only, it just takes moving all vac lines, harnesses, and brackets in preparation & rocking the engine forward (flat ground, or slight forward tilt helps alot).
Slip fits are a touchy thing to get right, but time and care usually prevails. The only thing about the location of the ones on the OBX/PaceSetters, is that there's 2 right against the firewall where you'll hear them. If you don't get both of them sealed 100%, I hear alot of complaints about the leaks.
I'd honestly consider buying one of the $299 sets of headers 2x over, before even looking at anything more expensive on the market (especially since you CAN buy at least 2 sets of them before reaching the cost of the others).
- Dave
