I have a Gibson Side-Swept system on my 2000 F-250 SD. Unfortunately, the muffler has developed a nasty rattle, which, according to Gibson tech support, may be one of the internal baffels that has come lose. As these things usually go, the rattle is loudest right around 35-40 Mph, where I spend most of my time driving through town - needless to say, it sounds like crap (kinda like my old Vega...)! Well, you say, Gibson has a Limited Lifetime warranty - so true, however, I have to produce the original receipt (wonder where that is?), buy a new muffler, have it installed, and ship the old one back to Gibson, who will then send me a refund for the cost of the new muffler (and how long will that take?)..... Needless to say, Gibson doesn't pay for the installation of the new muffler, nor the freight to ship the broken one back. Had I known about this site sooner, and run a few searches, I probably would have gone for the Magnaflow..... I wonder if Magnaflow would cut me a good deal to switch over...