Great for day hikes and as an under seat carry on. Did the southern Utah national parks and the it performed as advertised. Carried two water bottles in the mesh pockets, a larger bottle in the interior compartment along with a second pair of lighter shoes and plenty of snacks. The straps distribute the load quite comfortably.
As a carry on, I was able to carry my iPad, Kindle, snacks for the 4 hour plane ride, plus everything that has to come out of your pockets to pass through security. A small lap top would also fit in the storage compartment for the electronics.