I love this pack. I've had it for about two years now, and it's taken everything I can throw at it.
It's super comfortable, and rides well high up on my back for scrambling over rocks and hills, or lower for high mileage This really is a full size backpack shrunk down to daypack size. The frame, suspension, and load shifters all feel like they're from a weekend pack.
The pack itself is quite handy. The main compartment is decent sized, and has a divider between the top and the sleeping bag compartment. The hydration sleeve fits a 3L Camelbak or a 15 inch laptop. The bottom compartment is large enough for my 35 degree sleeping bag, but if I put it in a stuff sack it takes some wrangling to get it in there.
I?ve done a three day summer overnight on the AT with it. The pack fit my hammock, rain jacket, and food wonderfully. When I was working at a summer camp in Texas, I could fit a climbing helmet, harness, gloves, water, and ropes gear in it with no problems. At school, it eats my laptop, rain gear, textbooks, and pretty much anything else I want to put in it.
My only complaints are minor. It's not a pack for the super organized. The smaller pockets are useless for anything large, and if you cinch the pack down, anything in the pockets bulges out, making the pack look like it suddenly developed a bunch of headlamp and stove shaped tumors.
Also, the two main cinch straps run right over the water bottle pockets. Not bad, but if you put a Nalgene in it, it makes cinching the pack down tight harder. The pack tends to cinch out away from my back, instead of closer to it, but that's only when it's super full.
Overall, this is a great daypack/lightweight overnight pack. Highly recommend it, and will be replacing it with another one when it wears out!