I use a Platypus bladder that I ordered with my Kifaru G2 Longhunter and a 2 liter Camelbak Antidote bladder in my Eberlestock J34. I really like the big 1/4 turn cap on the Camelbak. It is easy to fill and the quick release hose makes removal and install a snap. I also like the hanger that is built into the bladder above the cap. That said, there is nothing wrong with the Platypus bladder and, neither bladder has ever leaked. If I plan to be out an entire day I sometimes take a Nalgene bottle for an additional supply of water.