Not bad, but I'd like something more secure on my waterbottles. Nothing is worse than realising that your nalgene is under the snow somewhere over the past mile.

I used to use an LL Bean pack of about the same size with a pair of pouches added to the oustide to carry my water bottles and FAK, but like others here have concluded, it needs shoulder straps.
At the risk of being called nasty names, I think they probably work better for women due to the shape of thier waist-hip region. *ducking behind cover* Particularly as when guys get plump, we put it around the waist, which makes it even more likely to slide down without support from above. *digging in*
Instead, I've come to like a chest rig that can be worn as a lumbar pack if you wish. That way you can have it up front if you are using a ruck, or in the back if you are going light. I know I"ve been promising pictures, let me shake it out for a few more weeks.