For those of you that use a dromedary bag on your alpine trips, what size do you use? Most of my trips so far have either been relatively short or have had good access to water, so no need to "stock up". But as I prepare for a summer in Peru, I'm thinking of swapping my two 1L bottles setup for a 1L bottle and a dromedary. I'm thinking 2L or 4L would be best, but would like to hear what the crowd has to say.

I typically use a 2 Liter bladder w/hose in the summer, unless I know the route will be long and dry (e.g. complete North Ride of Mt Stuart), then I bring a 3 L bladder with a hose and another 1 L w/out a hose.