i have a patagonia black hole and find it to be pretty sweet. the fabric is water proof, but the zipper is not. therefore it would be fine in the rain, but not submerged.
i can't compare to the others as i haven't used them, but i find the padded bottom, shoulder straps and lash points on the patagonia to be nice touches.
just so you know mine hasn't been on any crazy expeditions or anything, just general luggage use and roof rack duty.
if you need complete waterproof bags i would look at drybags from companies like seal line
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