I'll throw my .02c out here too. There is nothing more waterproof than a watershed. In seven years of using a watershed bag I never had one leak. On the other hand I had issues with a Nikon D200, for sure from impact, a Nikon D700 that I'm not sure if it was impact, and a D600 from impact while in the boat.Those are all with a blue sleeping pad foam liner and or other liners for lenses ect. My last year I broke the D600, the Nikon 24-70mm f/2.8, a Samyang 14mm f/2.8, and a Sony NEX-7.
Since then I've switched to Pelican. A nice mirrorless like the Sony A6000 fits in an 1150, or I can fit an A7 into a Pelican 1200. In over a year, no more broken lenses. Dryness I can't speak to yet, just one or two swims and no issues.