I use a GG Vapor Trail pack and have always used a water bottle in a pocket attached to the hip belt for drinking while hiking. There is a small side pocket on the pack and I was thinking about putting a bladder in that pocket. When I look at bladders they are all large (2 to 4 liters). I would like to use something like one liter which would fit in that pocket. I have a couple of one liter platypus bags and a hose to fit on the cap but I have been hesitant to use it because it looks flimsy and vulnerable on the side of the pack. Am I worrying needlessly or is something more durable available? Having only one liter readily available is not a problem since I would be stopping often enough to refill the external bag. Thoughts?