For the back pack I fit 15 in the bottom and 6 up top, but that's all I need up top. You can fit most likely twice that amount (6) up top. The bummer is, if you put to much up top. It pushes down on the bottom and makes the discs harder to get out.
If the Grip bag ever hits production (mid Nov?) and I like it better than my Revo dual pack. I'll sell it to you. I got it not to long ago and I'm not that impressed with it. They could have designed it alot better imo. Heck NO putter pouch or bottle holders WTF!