Do you already have the walls built, or a closet? You are looking at the Aurelex iso pack, right? It seems a little spendy for just the foam and some glue. Don't get me wrong, I use Aurelex myself (got a buddy who gets me good pricing at GC.) I put a bunch of Aurelex up in an apt. bedroom all over the walls and it was a nightmare to fix.
Good luck with your project flatnano601!