The only bad experience I had was with the Summit welded mufflers, but it was largely a matter of a salesperson that didn't know WTF they were selling. Back when I was muffler shopping for my '94 CVPI, I was looking for something with a straight-through design (like Pypes Vioaltors, Hooker Max Flows, Dynomax Ultra Flows, etc.), but I didn't feel like coughing up what was about $60 apiece at the time. The sales guy recommended their house-brand "fully welded mufflers," which looked on the outside identical to the non-stainless Dynomax Ultra-Flows. I got the things on my doorstep, and lo and behold, they're basically just really, really heavy versions of Thrush Turbo muffs. Barf.
I dunno if Jeg's house-brand exhaust has the same fitment problems as the Summit stuff, but I'm definitely looking at their off-road X-pipe. One may claim all they want about you get what you pay for, and there is a lot of merit to that saying most of the time, but exhaust parts can be so seriously hit-and-miss regardless of brand that it's really tough to say 100% of the time that any one brand never has a production issue.