I can travel without these now. Doesn't matter if I am going for a day or weeks somewhere one or more of these are coming with me. Makes everything easier, everything more organized. I traveled for 8 months overseas and was basically living out of these and all are still perfectly fine, no holes and no zipper malfunctions (and I stuff the hell out of them). The mesh on the top allows you to see what's inside and the carrying handle is convenient too. IDK these things are the greatest, got a bunch of other people on board already. They make fun of you at first until they start using them. If you are debating getting them and are reading this then just put them in the cart and thank me later. OH PS. I really like this pack style with the 4 mediums and 1 small. I have a 45L patagonia duffle that fits one full medium and a small on the bottom and can fit another medium on top and my 60 L patagonia duffle can fir 4 mediums no problem and I think even the small. I honestly don't think I would want a larger size than the medium.