After a nice little weekend outing with the new Atmos I figured I would give a little review here. We headed up Friday morning to Boundary Creek yurt in the Uinta's and really lucked out with the recent storm. We were the 2nd group into the yurt since the storm so there was plenty of fresh tracks to be had.
The first thing I noticed when I started loading the pack is how much I am not used to pockets.

My REI pack was basically a 75 L main compartment with a 5L lid, and I have been using it so long I knew exactly where I liked each piece of gear. The Osprey has so many different compartments that it will take a few trips to get my packing down. Careful packing and strap adjustment does seem to be important with this pack because it seems to get a little top heavy if not loaded correctly. I think this may be a function of the load of the pack being off of the back by several inches in order to allow the AG suspension to do its thing.
Once packed well however, it was easily the most comfortable pack I have work. I was 32 lbs. on the trail in. Overall it was a pretty short skin in (6.5 miles) and I had 0 issues with my shoulders, back or hips. Traditionally I see some very light bruising and rubbing on both my shoulders and my hips after a hike of this long, but had nothing on this trip. The pack was balanced well and really was a nice carry.
For the trip into the yurt we had access to a pulk sled, so I had my ski pack and all my avalanche gear on the sled. On the way out however we didn't have the sled. I stuffed my ski helmet into the main pack and strapped the ski pack (with shovel and probe) onto the outside of the Atmos. My ski pack itself is pretty heavy (over 4 lbs. dry) so I figure I had probably 6 pounds strapped to the back of the pack and a total weight of around 38 lbs. Because the majority of the trip out is light downhill skiing with just a few miles of skinning I wasn't worried too much about how the pack rode and kind of wanted to test the AG suspension with a little heavier and poorly packed load. With all of the weight on the back of the pack it was certainly top heavy and not near as stable as on the way in. The weight was much more pronounced as well, but with that being said, other than the balance of the pack it was still comfortable overall, and I had no issues in the 2 or 3 hours it took to get out.
Overall I was very impressed with the pack. It was hands down the most comfy backpacking pack I have worn. I would put its weight sweet spot around 25-40 lbs. Though I haven't yet carried it with a real big load, I would think the suspension would start to get overwhelmed if you started to get much higher than that. The overall quality of the pack also seemed pretty stout (zippers, fabric, straps, etc.), and was very much keeping with the Osprey design. Tons of pockets and compartments which will take some getting used to, but are pretty nice to have. I'm hoping I get at least a decade of good use out of this baby.
Sorry for the long rambling review, but there you have it.