I am having alot of gas too, I thought maybe it was from just having the surgery but I use the assura bags and they dont seem to be working as well as they used to. I usually have to (burp) my bag during the night too because it get so full it wakes me up and its mostly just gas. I think i might try the hollister. have you tried the osto ez vents? they are good to have, you dont have to undo the bottom of the bag they are placed on the top so its easy to just pop it open and let the air/gas out. I'm not sure what they cost, my insurance pays for mine, but if you'd like i could sent you a couple to try if you have to pay out of your pocket, i know they will send you samples too.
I Just tell myself, it could be worse !!!
"Even with a Bag!!!"