I love these bladders! I own a 3L hoser and a 3L big zip. I use the hoser in the winter with a regular platypus sqeeze cap on it (no hose to freeze). I stuff the hoser into my pack against the back-panel and it doesn't freeze. Plus, with all the air sucked out, it can be a small 1L bottle, or a 3L water buffalo. Durable enough for me- neither platy has patches both camelbak bladders do. These work great with gravity filters- I have a sawyer setup which is about as lightweight as possible for a gravity filter. Can't say enough positive things about Platypus!