I've used this for the past 5 months as a wet bag for my sweaty gym clothes and wet towels. It works great. The 30 liter size easy swallows a t-shirt, shorts, socks, underwear, bath towel, flip-flops, and my mesh shower bag. I could fit a second set of clothes and towel in there, too. All the moisture is retained in the bag - I throw it in my car after my workout and have yet to return to find frosted / fogged up windows or a funky smell. The bag has so far remained odor free (though I can't say the same for its contents).Originally I was considering one of those fancy decorative diaper bags. I just liked the Sea to Summit sack a lot better. I was concerned because the description says pretty clearly "not waterproof". That warning might be true for campers and kayakers where the bags might get submerged and knocked around. But for gym or beach use, I've never had a leak and am very happy.Update 03/10/2015:I've docked a star from this product, down from "love it" to just "like it".The bag itself has performed well and manages to stay odor free despite now holding my dirty, sweaty gym clothes for a good 5 hours every day. Except for what follows, the bag looks like new still despite daily use. The problem: The bag is a real pain to open and close now. Initially the drawstrings pulled nicely and the opening closed and opened smoothly. Now it takes quite a pull at just the right angle. The white plastic waterproof lining began shredding and coming out the drawstring holes and the opening got harder and harder to operate. Unhappy.