This is my boyfriends review of this item:
This pack is very well thought out. The pockets, mesh organizers, and overall architecture of the pack is on-point. You can fit a lot of stuff in there without it becoming too awkward. If you’re into the all day adventures this 15L is probably the right fit, if you’re in the max ~2hr bike ride camp I’d go with the 10.
I’ve used it chiefly for mountain bike riding, where it shines. It easily cinches down for a 40 min spin, or takes the food, rain jacket, and layers for an all day ride. While crushing the biking, it has remained comfortable on some long runs (8mi), and a number of long hikes (<20mi). It stays nice and cool with the mesh/open back, and the snack pouches on the hip belt are handy.
The shape of the pack lends itself to mountain biking, as it is more curved and conforms to the curve of the back while on the bike. Initially I had some sores/hot spots after my first long hike with a pretty full pack, but I later found I was riding the pack too low on my back. After adjusting the straps for a higher posture, the pack was much more comfortable for hiking and running.
I really like how the Big Zip bladder is integrated into the pack. The snap features do a good job orienting the bladder and they are surprisingly easy to manipulate when removing the bladder.
I really like how light the pack is by itself, but that also comes into play as a concern for its longevity. I’ve used it extensively for 4.5mo, and so far so good — I hope it keeps up, it's my new favorite pack.