Ive had an atmos 65 for a few hundred miles , and I find it very comfortable, distributes weight well.met a NOBO in ME in august who had the same pack, he said he had to replace the one he started with (which was several yrs old when he started his thru), but he stuck with the exact same pack, which told me a lot.I'm usually betweeen 25-30lbs w/food and water depending on the season.The only criticism i have is that when you put the bladder in the sleeve, it takes up a lot of space due to the curvature of the mesh back. some have put the bladder between the pack and the mesh fram, but I like to carry a 3L bladder and it doesnt fit.In spite of this, I still have enough room for all my gear.