I was using a Jim Horn Alaska pack and my buddy was using a external frame pack like the "camp trails" pack. After using several packs for sheep hunting now, I prefer the external pack frames. For scouting or even hunting I enjoy the soft packs, but for hauling heavy loads over up and down hill country, I prefer the frame packs. They ride your body better and dissperse weight over you body better.
Long range shooting is a process that ends with a result. Once you start to focus on the result (where the shot goes, how big the group is, what your buck will score, what your match score is, what place you are in...) then you loose the capacity to focus on the process.