I think i'm soon going to order an o/r H-pipe and install it to compare to the X-pipe. I love the way my UPR X/Flows sounds, but am very curious to how my car would sound with an offroad H instead. I'll probably pick up one off ebay for like $140. I just have to make up my mind that the sound difference would be noticeable enough to make the switch comparison.
Mach 460 stock sound system blows @ss. My bass is hollow and lumpy now, I think the speakers are blown. Anyways, I think the VRS and UPR x-pipe have similer designs. I have the UPR, which can be had for $139.99 off their site, and is said to produce very good power gains. (almost as much as a Dr. Gas)