Sorry, I didn't try on the Atmos 65; I simply no longer need a pack larger than 50L. There are two "tells" for the new model: the shoulder straps have a rip-and-stick panel that lets you move them up or down, and the hipbelt has two rip-and-stick panels (called "Fit on the Fly" that let you make the long (non-webbing) padded portion of the hipbelt longer if you need to.

It's worth looking around for. I found mine at the local outfitter's, and noticed that REI carries only the adjustable version. If you can't find one locally, just order one from REI, try it on at home and, if it doesn't fit, you can send it back for a full refund - all you're out is the return shipping, which may be less than you'll spend on gas trying to find one.