x's are really raspy. i love em, they sound evil, and flow better than an H.
if you want El-Cheapo get magnaflow or flowmaster catbacks w/ a BBK mid pipe. if you want it LOUD, go with magnapacks and an offroad mid pipe, or american thunder classic 40s and an offroad mid pipe. if you want it PAINFULLY LOUD (like how i like it) go with SLP loudmouth's with an offroad pipe, or just weld in race mufflers, such as those dynomax bullets or flowmaster 10 series coupled with an offroad pipe. And yes, having and not having cat convereters makes a huge difference in sound.