I really like it for my specific needs. However, keep in mind I'm not a avid backpacker, hiker, or adventure person. I honestly don't think I'll ever be carrying this pack for longer than 1/8 mile at any time. Therefore, I can't (and probably will never be able to) comment on the durability and overall comfort of the pack.
Previously, when my gear was split between two backpacks, I would typically pack one with what I thought I'd need and leave the other bag in the car. I viewed the other bag as a "back-up" kit. That said, I often found myself wanting to use a lens that was packed in away in the other bag. Granted, it probably wasn't very far of a hike to the car. Nonetheless, I usually played the lazy card and kept shooting with what I had at hand.
Consolidating the equipment into one pack leaves me with no excuses. Whenever I think another lens will work better, I have it right at hand.
Having used it for a little while now, my impression is that it isn't really designed to carry camera equipment and hiking essentials--it's designed to carry lots camera gear, and do it well. But that's exactly what I use it for...
I really like the paper thin DOF and the seperation from the background. I agree it screems for portrait work.
If you see me with a wrench, call 911