How stiff are the Pop Up frames? With respect to stiffness, how much different are they than wearing a full-blown frame pack às a day pack? I've been looking at the Pop Up as an alternative to wearing a load hauling frame all day, but wonder how much different they'd be.
Compared to full-frame packs I have, the MR 28 is more flexible and moves with my torso much better when walking. Seems to just slip through the brush and trees easier with less fatigue for me.
