I've had this out on the trail a few times now. The first was a day hike and there was ample room for a 3L bladder as well as a few 1L bottles. The small pockets in the compartments are great for organizing gear.
The second use was an overnighter. I was able to fit in my summer weight down under and top quilts, hammock, and tarp. Also took a pair of thermal leggings, extra socks, cook kit, 3L bla
This review was written in the old system and had content requirements that are different than reviews written today.