dual stacks off the pf

i'm getting a set of mbrp stacks on my truck next week once granwest get's them from mbrp,i'm just wondering if anybody has put a set on there new 6.7 off the particulate filtre and how does it sound and have they had any probloms yet with it just wanting to make sure before i fork out 1500$ for the set along with the tbar cover it sure looks good but just wanting too see what you guy's think thanks Dave