I bought the 20L bag and thus far have only used for several short day canoeing/kayaking trips. So far, it does seem water-resistant, items inside stayed dry during rain and when the canoe tipped over. I was able to fit camera and phone (in waterproof bag), 2 plastic water bottles, few snacks, sunblock and mosquito repellent (in a ziploc bag), an ultralight rain jacket (when not in use) and a ultra thin quick- drying full body towel with room to spare. I made sure sure to fold it 4-5 times to be on the safe side. I usually take good care of my dry bags, since I don't want to puncture them. I pay attention to where I set them down and I never throw them around. At this rate, I believe this will last me a long time. I love the straps on the side that allow me to attach a duffle bag strap in which I strap it on my back when dragging/carrying the canoe/kayak. I will definitely be buying more of these guys in different sizes when I begin going on overnight canoeing/kayaking trips.
I own the 5L version and it's a good little bag. What I like most about it are the straps on the side. Most dry bags do not have those. That way I can secure the dry bag to the outside of my pack and keep my valuables safe, dry, and easily accessible, all while saving space on the inside of my bag. Enough said.