I absolutely "get" the utility of these packs but I always come back to the thought that wearing one screams to nefarious types, "here is where my good stuff is" . So far I have resisted getting one.
I neglected to write that my backpack (Hyperlite ultralight) is made of Dyneema fiber which is touted to be very light and waterproof. Respectfully, regarding "waterproofing", I never trust just one system protecting my possessions hence the "compacter" bag insurance mentioned before.
Ditto: Even though my backpack states it is waterproof, I also throw in a plastic compactor trash bag so no worries-everything in the pack is in it. I don't carry anything on the outside that cannot tolerate the rain. It worked on the Long Trail and the Appalachian Trail also. Can't beat it.
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