I've really only diddled with myJX3.
On first look, I was very surprised at how comfortable it is on my back and as others have said, it feels lighter than it is.
I never thought of it as a system that I'd pair with climbing sticks. They almost always seem a mess in pictures of the JX3, plus more system weight. (Full size Beast sticks run horizontally off the back look decent...so any long in-line stacking double step stick would be ok I suppose...although it's a wider profile).
Nevertheless, I spent a few minutes "packing" LWCG compacts and I actually found loading them internally on those ground brackets reasonably smart. It held them in place extremely well and kept the load close to my back. It also kind of made an internal shelf for loose outerwear and a gear pocket to rest on (not that it's particularly consequential). While packing LWCG compact sticks this way does shorten the available internal storage dimension, it was still nice enough imo that I'd consider giving it a field test.
Without those feet, the sticks could lay across the webbing that connects the frame and seat and you'd functionally lose no storage space, or across the back of the seat as many prefer. But I kind of like keeping the edges away from any strapping and, again, the compact sticks kind of wedge in for stability on the brackets. If the brackets were at the same angle as the LWCG standoffs, they'd basically lock together.
Of course, like other methods, you lose some slimness through the woods and brush. It would be a problem in some spots but ok in others I venture to.
I don't know if 4 sticks would fit. 3 do. Pictured with two. (Also, I just grabbed the bulkiest outerwear I had lying around to get a sense of space and made no attempt at organizing better.)
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