I commented already two weeks ago in another thread the following. In the meantime we went on a 20 mile weekend trip. I carried 27 lbs with relatively full bear canister which worked fine in the Exo. But in my setup with a Z-Lite (10 panels) in the sleeve I felt like the distance between my back and the bear canister is a little too big. So for the next weekend I exchanged that for a 4-panel Z-Lite (and a NeoAir for a sleeping pad) and took it on a 5 mile hike with the same 27 lbs. That setup felt more comfortable. Both setups work for me, but I think I will take the two oz penalty of having the Neoair and the Z-lite seat pad instead of just a Z-lite sleeping pad -- the Exo carries heavier loads better for me in that setup.
I received my Zpacks Exo last month. I intend to replace my Osprey Exos 58 with it and take it on a three week trip on the JMT. The pack alone would save me over 1.5 lbs. Here are some observations based on short day trips of 5+ miles with my children. Once I complete several longer weekend trips I will decide whether to switch.
1) Bearicade Expedition fits and leaves enough space for other gear
2) Platypus 2l bladder doesn't fit with Bearicade at the same time in the pack (so I put it in a side pocket, which works well)
3) Sleeve for sleeping pad works well for my short Z-Lite (10 panels)
4) Carrying the bear canister without the sleeping pad as buffer is a no-go for me. So if I ever change to an inflatable pad like the new NeoAir, I would need a seating pad (Z-lite with 4 panels) as a cushion in the sleeve.
5) The stays are transferring the weight well to the hip.
6) Hip belt and shoulder strap work fine with roughly 25 lbs
7) Sleeping pad in outside sleeve works great as "cushion" for bear canister, but my back gets way sweatier compared to the mesh panel on the Exos 58.
8) Without sleeping pad (and without bear canister), I can feel the stays of the frame. May be better packing technique would resolve that. For me it is currently a non-issue, because my current sleeping pad fits well, but I wanted to see how the pack carries without the pad in the sleeve.
My initial impressions are very good. I need to put more miles on the pack, carry more weight (35+ lbs for 10 days without resupply on the JMT) and test the daily routine of getting this or that out of the pack and putting it back in. With my Osprey Exos 58 I have everything dialed in and went to Philmont, on the JMT and the SHR last summer - the pack works great for me. I got the ZPacks Exo in an attempt to re-evaluate my gear list and lighten up some more. So far I got my list for the JMT down from 17 lbs to 12.5 lbs (with 1.5 lbs saved by the pack). Since I have to carry some stuff for my daughters, there are limits to what I can save, but there is still room, if I would give up gadgets like GPS, Solar charger, etc.