I've tried out a lot of hydration packs. Mountain biking, trail running, hiking, mountaineering; you name it, I've probably had a water pack on my back, and of all the ones that I've tried from different companies, Hydrapak's Reversible Reservoir II is head and shoulders above the rest. I could talk about how you can turn it inside out (for easy cleaning) or how much I like the plug 'n play connector (that allows you to disconnect the...