I also bought the GB waterstone from Cutsforth on my last order. Have not used it yet. I too would probably not carry it on a trip where normal firebuilding was the plan. I would carry it and a file on a major trip (say a dream 2+ month canoe trip) or in the truck though. For my normal short trips I have not had to sharpen.

I have used sandpaper on a mouse pad for my edge work so far on all my axes.