I bought this pack because it is very lightweight, but I didn't anticipate a problem with the shoulder straps. They are sewn in to the pack and are NOT ADJUSTABLE! I am 5'11" and typically take medium sized things (such as this pack), but I was NOT able to get the weight off of my shoulders and onto my waist. I am a backpacking guide for my university and know how to fit/adjust backpacks and still had a problem.
That being said, this pack's design (aside from the shoulder strap not being adjustable) is great. The ample ventilation in the back is amazing and the pack is UBER lightweight! It is the 3rd Osprey pack that I have owned. I will be returning it, but will probably replace it with another Osprey.