Going To make a Change

X vs H will give you different tones but I doubt the performance difference will be noticeable, especially on the street. IIRC the H is better at equalizing pressure and has a smoother tone where the X is freer flowing and louder. Those cutouts are subjective - some like all that "noise" and some don't.. open headers are illegal in a lot of places so ya gots to be careful with them.