Initial positive impressions of the trick valve and snug, well-built horizontal holster faded quickly as I tried to put this to use in the real world. First, the valve: Hailed as superior to previous designs, it turns out to be utterly impractical under exertion as you have to deliberately suck the water out. Air is slow to recirculate into the slow-breathing design, and you end up losing your breath and your rhythm on the fly. The old point-and-shoot bottle, however simplistic, is cheaper and more practical. Secondly, unless you are desperate for a place to put your keys or goo (or have an aversion to running with anything in your hands), the holster is just overkill, especially for such a relatively small amount (20 oz.) of water. Last, but not least, insufficient cap threading allows for the top to pop right off if you tug it hard enough when drawing it from its holster and to leak if the bottle is squeezed. Ideal application would be for easy to moderate exercise: The holster keeps the water readily at hand when you need it, the valve prevents leakage and pops back into place with a quick flick, and the quality is sufficient for light duty.

The Excel HHS is a great product. The only problem is when you fill the bottle all the way, it bounces up and down on my back. But since I got the product at less than 1/2 of what other vendors charged, I can't complain too much!