ok i don't know about any other c/b but with bassani a prochamber sounds like shit. i like it 100 times better with my bassani o/r x imho. ive tryed both and i took the prochamber off within a week. maybe with chambered mufflers a pro chamber sounds good but not with bassani.i had an o/r h with my bassani as well and that sounded pretty good as well. so if you dont want an x just go with a o/r h.
do you got a clip of your o/r x?