I've got several Kifaru packs, a Molle Express (same size as a spike camp but with PALS webbing to attach stuff to it) a ZXR, a Scout, and a Duplex with a Cargo Panel. I just bought a Grab It on eBay. I think the ZXR is quickly becoming my favorite, 3,700 cubic inches without extending the collar, 24" stays. It's got a little more robust suspension and is REALLY comfortable with 70lbs.

A hack for you Spike Camp owners: for carrying bone in quarters that won't fit in the main bag, unzip the bottom zipper, and set the ball joint end in the bottom, then have a few straps/buckles to lash it to the pack. This picture shows my MollEx in head to the pool mode with a 6 pack, just to give you an idea...

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