I'm a big MR guy. I currently have a Selway 60, Pop Up 28, Mule and a Rip Ruck and all 4 of them are perfect for what I use them for. I owned the treehouse, sold the treehouse. Didn't even go up the tree once with it. Its awkward, heavy for what it is and theres just better options out there. I truly just don't like the pack.
If you are planning on packing out whitetail meat - yes, the Pop Up 28 is perfect - its a perfect pack for hauling whitetail. But if you have atv access to a kill, or drag to a road - Id go with something else. If you are hunting anything larger that whitetail, Id get a true meat hauler on the guide lite mt frame. As stated above, depends on if you are packing your stand in and out.
The best treestand pack Ive found has been the Eberlestock Bandit. Its compact, has enough room and you can lash gear to the outside in between the molle panel and is durable as hell. The one thing Ive learned about whitetail treestand packs is, the bigger the pack, the more unnecessary gear youll put in it. You don't need a ton of gear to treestand hunt. The bandit is big enough for me to take what I need, and small enough to where I cant pack 2 thermacells and 4 pairs of gloves and 3 copies of War and Peace. If I were to take my Selway up a tree, Id somehow find 60L of gear to put in it. Youll find things just because you have space.
If I'm packing in my Lone Wolf, Ill have shoulder straps on the LW and I attach the bandit to the back of it by the carry handle on a carabiner and a rubber strap to keep it tight against the platform.