The belt is very light and comfortable and did not inhibit my arm swing at all. The bottles were easy to get at and drink with on the run. Well, one of the nipples is a little sticky. With two bottles you might think it would be great for long runs, but be aware that the pouch is really small. My smartphone just barely squeezes in (with difficulty) leaving no room whatsoever for food, keys, or whatever. If this belt was designed by runners, as claimed, those runners clearly didn't require much in the way of storage. It's too bad - I really wanted to use this for long training runs and marathons, but it is totally unsuitable for that if you want to carry any reasonable amount of nutrition, keys, etc. in it. Tips to the manufacturer: 1) the belt narrows where the pouch is! 2) If you really don't want to make the pouch taller, you could have made it more expandable. 3) You could have expanded outward by making a double-decker pouch. 4) With a bit more of a redesign you could put additional pouches on the sides of the belt. Bottom line - if you want a top-rated belt, make sure there is room to comfortably fit a smart phone, keys, and some nutrition. I have an old, cheap Nathan belt that can handle that. Guess I'll have to keep using it.