I have bought two of these--one for myself before a camping trip and one for a gift. I was concerned about how sturdy it would be once filled but it's fine. Granted, I wouldn't squeeze it, but as long as you're just normally drinking, it's handy. I liked that this came with a pill container that separates from the lid. Additionally, you don't have to worry about it dripping all over your bag once you're done using it if it isn't completely dry. The gift one I bought was for my mom, who had once purchased a traditional collapsible cup...this is far and away better than that I remember having those as a kid, and they're fun to open and close, but hard to keep open when you need them to be! I am now considering getting a small version. It is a bit on the large side. I don't carry it around daily, just for traveling, but if I had a smaller one, I might use it more.