To mention...with all my trans/engine related issues, I've pulled that front exhaust slip joint apart 5 times lately. The SLP'* that I have are taking it great and there'* no leak that I can find.

Silly question, but if you had full high-flow exhaust, headers, and a custom intake wouldn't that help you out either way? Any of the headers should produce better flow than stock... combined with larger pipes, hi-flow cat, hi-flow muffler... and of course, an intake. (or gutted box)

I added the intake into this one, since you can pull air in faster, but it doesn't matter if you can't push it out faster. lol.

Anyone correct me if I'm wrong though! I'm using my experience with cars in general on this one...

You're right about better flow... even with a questionable set of headers, you're flowing quite a bit better than stock manifolds. In our cars, a better cat-back system isn't even necessary until you get really serious with your mods. After a high flow cat, the stock pipe and muffler are fine until you get well over 300hp.

But if you're looking for the best performance, you want quality headers that will flow as well as possible. Not necessarily a large volume of air, but also an appropriate velocity. Small defects in craftsmanship will hurt velocity and volume, and while the effects may be small, it kills you know you might be able to get a tiny bit more out of your setup.