The TRD exhaust, from what I remember of the tC one (haven't heard it on the xB yet) is a little higher pitched than I like. I went w/ a Magnaflow on my tC, which was lower, but more quiet and a good muffler shop could probably make it more so. AFAIK, any header will be loud and is why I never went further than I/E on the tC. And many intakes can be quiet at low RPMs but get loud when you get on the gas... I'm not sure how much that helps you, especially since I haven't done I/H/E on the xB & don't know when/if I will (priorities).