JollyRoger
WKR
I dont know that I would need something like this, but it does look like a cool pack for quick hikes. As for using it like a lid/add-on pack... Kifaru has done this a lot in the past. At one point I want to say all their military line packs could be docked to eachother. The idea was you could have an MMR or EMR as your ruck and a Marauder attached with your assault or med bag kit. Set up your TAA, grab the assault bag and move out.