Both use 3/4" gate keepers with 3/4" webbing so it is easy to attach a Kuiu bag on the SO frame. You can attach a pack bag that uses 1" webbing (e.g. Kifaru) by creating connectors to attached 1" webbing to the 3/4" webbing loops on the SO frame. You can do this by using 1" gatekeepers - see the...
When Kifaru came out with the 22" frame I sold my 26" frame and have never looked back. I did it for the same reason as the OP - the 26" would get caught in low branches and stuff. I sewed some stay pockets onto the frame so I can extended it to 26" with some short carbon fiber arrows for meat...
The E&E has 2" shoulder straps or you can attach the X-ray shoulder straps. The Urban Ruck has the X-ray shoulder straps while the Bane has 1" shoulder straps.
I think from a comfort point of view the Urban Ruck and E&E would be more comfortable than the Bane because of the wider shoulder...
I've been hiking 5 days a week with this pack in October and I think it is the best internal frame pack yet from Kifaru. I've had the Late Season, Siwash, KU 3700, Marauder, Timberline, Timberline 2, and a Tarryall and the 357 Mag is better than all of them. I like the bag layout and suspension...
I cut my Seek Outside frame to 22" using a pipe cutter and can easily add the 4" extensions to get 26" frame for hauling meat. I'm using a KUIU Ultra 4000 for a bag. Weight come in under 4 lbs. Could use a seek outside bag as well such as a Fortress 4800, Short-Tail, or Peregrine 3500.
The wraptech belt is not the same as the duplex belt. You might be able to get a duplex belt to work on a Late Season if the duplex belt has stay pockets. It looks like the latest duplex belts from Kifaru don't have the stay pockets anymore. A wraptech belt will not work on a duplex frame.
Search youtube for Hungry Hammock Hanger. He has a bunch of videos on making your own dehydrated meals.
Here's a link to one of my favorites: Beef Stroganoff
I have the older 4000 and wish the middle zipper front pocket was bigger. It sounds like the new 4000 has a larger front pocket. Would you say the new 4000 has more space overall than the old 4000 (I'm assuming the main compartment on the two are the same size)?