I hike mostly desert and Platypus bags are the bag of choice. I like 1.5 or 2 liters.
I replace the caps with pull valve caps off spring water bottles to guard against spillage in case I knock over an open bag.
I did puncture one once. I stumbled fell against an ocotillo plant(very thorny). Noticed my leg was getting wet and thought it was blood at first. REI replaced the bag, no questions.
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paul, texas KD5IVP