is their really a difference(H-Pipe)?
 

on this page http://v6mustangstuff.com/XPipe.htm is their a difference between the MAC H-pipe and the $100 custom one?

nope but remember if you get an off road (O/R) H pipe which just means it doesn't have cats your car will not pass emissions testing. Depending on where you live this may or may not be a problem.

EDIT: It might be made from a different material that could rust but who knows

mmmk thanks a bunch :) and yeah i doubt that law will matter any where i live lol.

I would be careful about "custom bent exhaust" as its probably not mandrel bent sooo.....in all bends the pipe is kinked which restricts flow..less horsepower. Kinda the idea of a garden hose or a straw straight flows great as you bend it inside kinks with mandrel bent it is same dimensions inside even around curves/bends. https://mustangboards.com/images/icons/icon3.gif