I have all 3 (Joey, Little River and UD 25L). I’ve carried up to about 18 lbs in each. I find all better with under 15. The UD is definitely the most supportive. The heavier fabric and foam panel help. None of them fit like a Salomon running vest. In terms of volume, one man’s 25L or 30L is not another’s ;-) I think I would rank them as far as space: Little River, UD 25, then Joey. They all jog/ultra shuffle pretty well, but if you’re “Running” though they will bounce. I prefer the top closure on the Little River. I slightly prefer the fit on the Joey, it seems slightly closer to my back and rides a bit higher in relation to my shoulders. I slightly prefer the “Front” pocket on the Joey; the Little River combines the side and front pockets. My trips max out at 4-5 days w/ these packs. This is stoveless at that # of days w/ a compact kit. Of the Joey and Little River, I tend to think the Little River might be a bit more durable as far as bush wacking, etc.
I wish I could combine all 3. Straps and fit of Joey, materials of Little River and stiffness stability of UD… and I’d be willing to have it an ounce heavier to have a dry-bag-ish main compartment (liners are a pain).
I apologize for the long answer w/o a “Buy this one.”
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