OK here it goes. I recently got a "Hydration compatible" backpack. It is an early Father's Day gift in time for the Ham Slam. I think it will work out great. I have always carried a couple of water bottles but I picked up a 70 ounce camelback bladder to use instead. When the bladder is full it becomes kinda cylidrical and makes the pack a little awkward. This is a bladder only. I also saw some "pouches" that are made specifically for bladders. Do i need to put the bladder in one of these and then put that setup in the hydration pocket? Also, has it been your experience that 70 oz is enough or should i get a 100 oz instead? is the extra weight worth the extra water? Thanks, Tony