I used the Essence for 5 nights this spring in the NC mountains. I was very happy with it. I use a full length 20″x70″ 2″ thick pad, which isn’t ultralight, but fit well in the pack and was very comfy as a pack frame. Frankly I wish the Essence was a little bigger, so I could fit more puffies into it, but with a little study I had no problem with 13lbs base weight, 5lbs food, and on occasion 6lbs of water – 23 pounds max weight I carried up to dry ridge camps. I found it very comfortable, I did add my own sternum strap. With my pad I could get a majority of weight on my hips when I wanted for a break. The waist pockets are great, I put my heaviest gear there. I think they could be bigger. My lunar solo fit along with a liter soda bottle in the large mesh pocket. With study and practice a lot of little things fit into the top pocket, but I agree with above that a zip on the back would be better. I couldn’t really reach the front zip while hiking.
I give it two thumbs up. The weight savings from a 13oz pack was a revelation.