my wife just got a camelback and loves it, we put a first aid kit and some doggie treats in it. (treats for our dog, he loves to run on trails, also throw the treats to divert the attention of other dogs) i don't drink much water so a bottle is still good for me. also lower maintenance if you use bottled water or 20oz gatorades. but i've been considering getting a camelback and then get a frame mount bear mace for possible bear or dog attacks, and the increasing occurance of random violence in my town.