I used Sea to Summit Lightweight Dry Sacks when I hiked everyday for three months and these were great. They held up really well. I used them in my pack. They compress easily. I used them as food bags, and hung them as bear bags--even in the rain and my food stayed dry and uneaten by mice or bears.
I used one of these for 3+ years on every trip I took. Great for storing clothes and electronics. I took it on every climbing, hiking, caving, and kayaking trip and it stayed in basically brand new condition unil it finally tore because a friend's dog thought it would make a good chew toy. Sea to summit dry sack: not dog proof, but will stand up to nearly everything else.
"this is about keeping your stuff dry. that's the bottom line."
i bought several of these for my 4-day kayaking+island camping trip in NC and loved how easy they were to close. I had been skeptical that they'd leak somehow (well, I was skeptical of the closure mechanism and fabric) but they proved to be impressively durable, strong, and well designed. Cudos to such a simple yet effective design.
I've got a whole bunch of these in all different sizes for when I go kayaking. The 13 liter size fits great through my round hatches on my NDK Romany and Tahe Greenland. They keep my stuff dry and don't weigh much. For backpacking, they would last a long time. For kayaking, things often rub around but all of mine have seen a lot of action and none have sprung a leak yet. Good stuff. I use them for backpacking too.
"I'd trust it with my prized stuffed pheasant collection"
Well it's Australian designed so you know it's going to be good. We trusted $1000+ worth of camera gear in one of these when we capsized our canoe. Came up without a drop. Has a white inside lining that makes finding what you need easy. I'm about to buy a bunch more.