Just used this pack for a 4 day 6 mile hike with 4 little kids. Packed tons of gear, probably 80+ lbs. It really expands well on the top as you keep adding things. You can add a rolled up item on the outside lower back with some cinching straps(blanket, air mattress, probably up to 12-16" diameter, fairly lightweight, probably not a good place for a tent). Shoulder straps & waist belt very comfortable. Vertical aluminum stays can be bent to fit curve of your back. I'm 5'5" and I adjusted the shoulder straps (adjust in relation to the waste belt) to "S" (small). It will go to "XS" and three larger sizes as well. Easy to adjust size & bend stays (unloaded pack over your knee, or take them out).
On the way in, I had the pack too large and stays not bent out at lumbar area and it got pretty sore. Also overloaded the small waste pouch and got a sore spot there. At camp, I adjusted the shoulder straps to "S," bent the lumbar area of the stays out, and took the small binoculars out of the waste pouch. Then this was a breeze on the hike out.
Seems & zipper seem good quality. Fit large 0 degree LL Bean mummy bag into the sleeping bag area on bottom with no problems (about 2 minute stuff time). I like the side compartments which I used to hold ~30" tent polls in one side and 5 fishing poles in the other! They really paid attention to detail on this pack and you don't really appreciate most of what it has until you load it and get down the trail. New & empty, it looked a bit confusing with all these buckles & stuff hanging off it. Once loaded, it becomes pretty obvious what goes where. You have to load it to adjust it (I used a 50 lb bag of rice, which worked so so), although you will still be adjusting things on the trail as you figure it out.
I'd buy it all over again, although I'd consider the next size up as a father with 4 little kids. I think it will do fine though. Seems lightweight.