I have like, 400 sqft of bquiet extreme in my suburban, this stuff works better than dynamat xtreme, and I've used dynamat products for years. It's just too expensive to use that much dynamat when the bquiet stuff sticks better. DO NOT USE THE INDUSTRIAL STUFF. It will peel off and doesn't have near the qualities of real sound deadening stuff. It is not designed to be applied to surfaces which are not flat and clean.. and it's brittle. You need the extreme series mats, stuff which has aluminum backing and a really ridiculously sticky tar. Also, overlap all your sheets/pieces. roll down every bit of it with the roller.
my favorite deadener of all time is expanding foam. Nothing strengthens a car better (maybe cement. Actually definitely cement)
expanding foam can't be used in as many places as a good sheet mass loading deadener, however. I like to use the proper deadener in teh proper locations for best effect. For example, foa in teh trunk lid, covered with sheet deadeener. spray rubberized undercoating on the door skins. foam in the rear quarter panels and in the trunk behind panneling. cloth padding for interior panneling. etc
edit: I like the aluminum backed stuff too, but it can be a real problem in doors where resonance from speakers can cause isues with cone motion. I dont even know if thats the cause. but aluminum backed deadener might cause you problems in the doors behind the speakers. I like it especially for the trunk lid over the foam though, the aluminum provides a surface to put a cosmetic covering over.