Karen wrote a review of MSR Dromedary Bags on August 24, 2015
Familiarity: I've put it through the wringer
I don't know about you all, but I love water. As compelled by this love, I consider my drom to be one of the most important pieces of gear that I own.
It's lighter than water bottles, more packable, and has a greater capacity. Plus, these things are tough as nails. I work as an outdoor educator and I've seen these droms survive 10+ years, with hundreds of field days each year, and that's with teenagers using them.
I've heard a couple of complaints about them, specifically 1) that you still need to carry a water bottle to fill it and 2) that the caps are prone to leaking. I find that 90% of the time you can fill these most of the way without another vessel. Even when you can't, you likely have a thermos or a pot that you can use to top them off. As for the caps, I've never had one leak on me and I've never seen one crack or degrade. I have had friends get defective lids that leak from the get-go but MSR has always been great about respecting their quality guarantee and replaced them on warranty. (Also, a fun fact about the MSR lids: they are sized the same as nalgene products. The large lid is the same size as a water bottle lid and the smaller nozzle is the same size as the 2 oz spice/liquid containers that they sell so you can replace them on your own or put an emergency cap on if you're in a pinch.)
Also, these droms have more uses than just replacing the use of water bottles. They're key for dry-camping and even when you're just the standard 100-200 ft. from your water source while camping, I love keeping a store of water at hand for cooking and hot drinks. These are also the best back-country hand-wash system out there. You can hang it up in camp and keep norovirus at bay without rinsing soap or your nasty-human-hand-funk into your water source.