Product review (5 stars): Good for rafting/camping
I used these inside dry bags and a backpack on a 2 week river rafting trip in the Yukon. They held up very well through a lot of packing and unpacking, and kept all my stuff dry. Not HUGE, so better for a backpack than a full dry bag - but I just put 2-3 separate ones per duffel-sized dry bag, and it worked great.

Did not tie off, just folded over, so can't speak to the twist ties. They looked okay but not super reusable.