I'm using a mountainsmith frostfireII and I can adjust it so the loadlifters work properly. Can't do that with most packs. 6'7" 260.
I have a Dana Bighorn that I prefer for a daypack. It is a medium or small and I like it partially because it stays below my neckline and allows me to use my safari sling without getting in the way. Still can carry it ocmpfortably all day. Kind of a "big" spike camp type pack.

Here's the bighorn.
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