The lowest price on a Revo Dual pack is $145 (the lite model) and the entry Grip is $200. I'm not spending that much on a DG bag. $50 the most I'll drop on one. The Grip bag holds 20+ discs I got 16 in mine with plenty of room for a few more.
Also, all backpacks on the Grip & Revolution sites are "out of stock".
This seems to be a good and not too expensive alternative and if it doesn't work out for me it will make a great overnight travel backpack.