Here's my third try and I like it reasonably well: the Amphipod RunLite. Actually the one I linked to comes with four bottles, the one I bought has three and most of the time I use only two. But that's one of the great things about this belt: you can easily add or subtract bottles and pouches, move them around so they're balanced and out of the way of your arm swing, and you can orient the bottles valve-up or valve to the side. The belt comes with 8-oz bottles but it will also accept Amphipod's 10.5-oz water bottles and 4-oz gel flasks.

I tried a handheld Nathan bottle. I think two would be better than one for balance reasons, but even so the extra weight makes arm swing difficult; it seemed like it was giving me shoulder problems even when I switched from one hand to the other every mile; and the valve leaks (so I always felt I had to put my phone in a ziploc bag inside the pocket). But it's secure and comfortable on the hand, and if you want it it's yours

I also tried one of those belts that holds a regular bottle at an angle at the small of my back. I forget the brand. Bounced like crazy. Could hardly rotate my pelvis. Took it back.

The Amphipod belt has to go at your natural waist to avoid bounce - so it looks really dorky, especially if you're short-waisted like me. It has a bit of "give" to it so it doesn't bounce or restrict my breathing. The bottles are very secure when they're clipped in correctly - that's my only real ding on this belt, is that the bottles can seem like they're clipped in when they're not, so they fall out. Maybe that just takes more practice - I've only run in mine maybe 5-6 times, and I get it right most of the time. In the other direction, the bottles are easy to take out (just squeeze in the direction of the clip, they're slightly flexible).

The only other thing I don't like about this belt is that there's not enough size overlap. A medium was really too big for me, but if I gain any weight I won't be able to fit in my small one. But I'm between a small and a medium in most brands, so hardly anything fits right