Ummm i think u mite have that mixed upp...ORH pipes give u a nice deep tone. And the ORX pipes give the raspy scream at WOT and the popping when coming down the RPM's. And from what i have herd in the HP department the X makes more than the H but not by much so its up to what you what it to sound like.
as a person that went with both, I originally had the bassani catted x and switched to mrt catted h about 2 yrs ago. You will not notice much of (SOTP) seat of the pants difference. The X-pipe will give you slightly higher peak hp. and the H-pipe will give you slightly higher TQ. Bottom line comes with preference of sound. X-pipes gives a more raspy sound while the H-pipe gives a more deeper throaty muscle car sound! For me...I love the way my H-pipe and borla sound!!
H pipe is a great sound and tends to not kill the low end torque so much as an X with modulars, you will feel the loss in the low end if you go with a catless setup, the H helps that a little, if you get one with cats it will help your torque at the bottom, I noticed on a friends GT when we put a catless h on it, it gained top end, but seemed to fall terribly short below 1500RPM it just didn't have the torque it did before....my 5.0 I installed a catless H on it and it actually helped it alot above 3000 RPM or when I was in boost. but below 2000 RPM I didn't feel any kind of power loss the way she and 2 others I've done (modulars), have in the low end
Thanks guys, I kind of heard the same x-pipe gain higher but lose lower, h-pipe gain lower but not too much gain on higher. I'll stick with the h-pipe, I like the throaty sound anyway.