Needed a light hiker for an 85 mile straight through hike (completed in 35 hours!) Could not afford something heavy or ill-fitting. These shoes totally rocked! Changed socks twice (Smartwool PhD's) and to be honest I never even had to think about how my feet were doing. I purchased 42's and I usually take between an 8.5 and 9. Used the standard insoles which were fine after a brief break in period. Tongue is padded like crazy and you never feel the laces coming through. I have a medium width foot and toe room was great vertically and horizontally. Grip is fantastic. 100% love these shoes!
I ordered a couple of the small Atmos 65's from SAC for my scout age boys. I loaded them up with about 30 lbs and not matter what I did the load seemed to pull straight back on their shoulders. I had seem some reviews about the suspension pushing the weight too far off the back and I could see what they were talking about. I was wondering how Osprey was even selling some of these bags. A buddy of mine had ordered a large at the same time and we got together for a short hike and I asked if I could try his out. He had it loaded with 35 lbs of gear and when I put it on I couldn't even tell I was carrying anything close to that weight. It was night and day from the other model I had tried. So bottom line, the air suspension seems to have a bigger affect on the load balance on the smaller model but if you are looking at a large (and I have a 19" torso and 31" waist and it fit me great) then this is an amazing pack.