We use it for a couple of our pet rats that didn't seem to do too well on pine pellets. It works pretty good, but Equine Fresh seems to do just as good a job on the smell (with rats anyway) -- and at $6/bag for Equine Fresh or $15-20/bag for Cell Sorb, well it's just not cost effecient. You may want to give Equine Fresh a try, see if it reduces the smell enough in your room compared to Cell Sorb.
I've used Woody Pet which is similar to Equine Fresh. It was excellent. The store that carried it was so far away that I just never went and got more. I'll check to see if anywhere close carries Equine Fresh. Thanks!