I have been looking for better hydration options. Currently I am drinking out of public (some private) faucets and doing water drops. I hate doing water drops! You have to remember to do it the night before and then you should go back and pick up your trash the next day. Also, I hate having to come to a complete stop so much to get water. Granted I love the stop on my long runs BUT you do not get water breaks at marathons and I feel like it does not give me a real feel for what my time could be. So I had to decide between a handheld or a belt. I have some back issues and get annoyed with my Go Belt every now and then so I went for the handheld. I bought the smallest water bottle I found on amphipod's website (12 ozs.) and I think it was a great choice. Any heavier and I think it would have been too much weight. I also liked the curve in the bottle and feel that helped with my hand NOT cramping during the run. The only bad thing that happened was when I filled it back up at a faucet I let the pouch get wet and it absorbed water like crazy so it dripped water on me for the last half of my run. Not that big of a deal and I will be more careful next time. The pouch is a good size and could hold 2 GUs. I would not put my keyless entry in it since it is not water proof. I love the bottle and plan on using it for the rest of my long runs. I would even consider using it on at a marathon if I though water stops would be crowded. However, 12 ounces is not a lot of water so I would need to be able to refill it at some point at a marathon or stop at some water stations. Great product and I will use it for sure.