I don't like the sound of x-pipes but they work well. I run a 3" Dr Gas X with Magnaflows dumped. When I first got the Dr Gas X I had 3" Mac Pro Dumps. It sounded like crap to me. Way too high pitched and raspy. The Magnaflows helped it get a little deeper tone but still not the kind of sound I like. H-pipes sound much better in my opinion. I'm not giving up my X though -it makes too much power in the high rpm ranges to switch back to an H.