This is a late response, but…
I have two of the Dana Design Wet Ribs (from before they were acquired by Marmot). Correction, since my wife won't return one of them, I have one (a large). She has the smaller size.
Both items are among the "most favored" list of my gear and enable me to keep a number of handy items just under my rib cage. The wet rib includes a bottle holder (drawcord top with mesh bottom) at the end of the zippered pouch.
The Wet Rib (at least the Dana version) is NOT designed for light weight but rather durability. I can carry a full size Nalgene or equivalent, camera, gloves, snacks and a folded map without hassle. The straps are effective at holding the pocket close (just under my rib cage) where it doesn't impact my arm swing or view of the trail/ground.
When I use my hydration bladder, I use the water bottle pouch for other items (bandana, knit cap, etc.).
Though the pack cloth is PU-coated cordura, neither the zipper nor the seams are sealed. If you truly need to keep the items carried there safe from water in more than mild rain, then zip loc bags or something similar are needed.
I tried to order another one last fall (from Marmot) and was informed by the retailer that the entire supply chain back to the mfr. was depleted with no scheduled production. I have run across some of the Dry Rib pouches at a local retailer, but not the Wet Rib. Hope this helps.