I have been using the Atmos AG 65 all season and over all I really am happy with it. A few quick details on how I have been using it. A total of 5 trips been from 8 to 12 miles per trip, usually one night, pack weight was 35 lbs on the low side and one trip around 50 lbs. The harness and compression system provide for a very comfortable, stable ride on the trail.
Here are some specifics I think other shoppers should be aware of.
I had been back packing with a Gregory Forester and the difference in on trail comfort is hard explain. The Anti-Gravity suspension is with out question the most comfortable suspension system I have hiked with. The mesh back panel is cool and provides a great cushion under load. For me, comfort with the harness and suspension system made up about 95% of my decision when I was making a decision
The over all build quality is excellent, as expected. Premium materials and construction result in pack that should last for years
There are plenty of storage pockets and gear attachments close at hand allowing for excellent organization when packing
Trekking pole attachments are really well designed and the shock cord tie outs hold the poles in place securely
Large mesh pocket on the front is great for stashing maps, binoculars, rain gear, etc.
The zippered pockets on the hip belt are tricky to close, once zipped fully open it requires 2 hands to close. One hand to pull the zipper and the opposite hand to hold the end of the zipper to create the needed tension.
The mesh pockets on either side are large and have openings on both the tops and sides, however they are really difficult to use while wearing the pack. I use these to hold external water in Platypus 1 litter SoftBottle's. Usually I have to have one of my kids stuff them back in until the SoftBottle is about half full, then I can wiggle it in myself.
The bottom of the pack itself curves up and away from the hip belt creating an rounded bottom. When you take the pack off, you have to lean it against something with the suspension system facing away from whatever you are leaning it against in order for the pack to stand upright. Not a big deal if you are just taking a break on the trail, but not great when you are in camp and are getting in and out of the pack.
As I mentioned above the comfort and fit of the harness and suspension system was far and away the most important decision factor for me, and this pack is at the top of the heap, no question about it.