The first thing I would look for in a large volume pack is a comfortable frame that is capable of 100+ lbs. After lots of web searches and reviews I had it narrowed down to Kifaru or Stone Glacier. I ended up with Kifaru for several reasons. I hardly saw a single bad review. The padding on the belt and arms is tough to beat for comfort. Once you have a Kifaru frame you can interchange a large selection of bags, pockets, and accessories. Stone Glacier didn't offer camo patterns...which was the deal breaker for me (Kifaru offers a number of great camo patterns).
I've had mine on 7 different Alaska dall sheep and mtn goat hunts, numerous Colo/Wyo big game trips, and also use it for hauling large volume turkey decoys (and toms). It has performed flawlessly. I've had plenty of room in my EMRII bag for camp, rifle, spotting scope, tripod, gear, plus lifesized capes and meat. The guide lid is huge and works fantastic for quick and easy access to raingear, extra shells, snacks, headlamp, etc. The materials are super strong and have held up to super rough treatment in rugged terrain, in super wet, nasty conditions. Kifaru has a lifetime warrantee...which I doubt you'll have to worry about!
The EMRII bag is super long and narrow so the load is kept close to the frame and your back. A large elk or moose hind quarter fits with room to spare. I really like the side pockets and pouches for quick and easy access to spotting scope plus tripod. Plenty of attachment points and options for rifle/bow. I have a smaller Timberline bag that's a great set up for day hunting....but it pretty much collects dust. I would rather cinch up my EMRII tight and be prepared to haul out a large volume load the first trip.
