The backpack is sturdy, well made, the seams are fine, the MOLLE straps and the cutouts on the front are of good quality. So far, the zippers work flawlessly. I don’t know where the 51L capacity comes from, because it’s definitely not that much. The real packing capacity is around 38-40L. But without overstuffing, I managed to fit inside: a 2-liter water bottle, 3 bottles of drinks (0.33L), 1 bottle of isotonic (0.5L), a hammock, 2 small sitting mats, a large foldable Japanese saw, a WZ food ration from Arpol, an extra small food portion, a large raincoat, 1 set of underwear + combat shirt, hygiene kit, insect repellent, thick tactical gloves, a map case, 5m of 4mm rope, a metal mug, and a roll of toilet paper. I attached small EDC items to the MOLLE on the sides. I really like the solution on the ends of the compression straps—after shortening the strap, you just fasten a small Velcro and nothing gets tangled or hangs unnecessarily. In my opinion, there are 3 minor downsides: 1 - I’m not short (180 cm), and after fastening, the chest strap was right on my neck. I had to move it on the shoulder straps, which isn’t easy, because the straps have stitching and you have to force them through the buckles. The second minus is the hip belt—it does its job and the backpack doesn’t “dance” on your back, but it could be wider (it’s just a regular strap like the chest one, only slightly wider). The third thing is that the lower straps are a bit too short. A small mat will be fine but anything bigger and they’ll be too short. Despite all this, I definitely recommend it because it’s a cool, functional, and quite decent backpack.