Grayson wrote a review of Osprey Packs Aether 70 Backpack- 4000-4600cu in on October 27, 2013
Familiarity: I've used it several times
I bought one of the last 2012 version packs just under a year ago. With it I have been on 3 multiday trips, dealing with snow, desert, and summit ascents. I love this pack. 70L is *plenty* to fit your multiday gear in. If you are a light packer, it allows you to cinch down the extra space nice and tight. The adjustability is second to none; giving you control over the weight distribution and comfort. It is not one of the lightest packs, but it can take a beating. You don't have to worry about rips or tears, especially with Osprey's lifetime warranty.
While I do not own the 2013 version (not yet), I have tried it on and can say it's definitely more comfortable than the previous model. I had a similar experience with another reviewer here, Johan, in not getting fitted correctly, which definitely adds some discomfort and frustration. But the new isoform belts and shoulder straps feel great, I am looking forward to upgrading to the current model.
The Aether is a great pack for anything from weekend to multiday or extended trips. You can't go wrong with this pack!