Ashley M.wrote a review of Sea To Summit Ultra-Sil Nano Dry Sack on July 28, 2015
Familiarity: I've used it once or twice and have initial impressions
I'd been wary of adding extra bulk to my pack / panniers with these bags, but bought two to help with organization. They are incredible. Haven't yet tested the waterproof nature of these, but I've used the 13L as a sleeping bag stuff sack and my down has kept nice and dry.