This is the best pack I've owned. I just used it to summit Mt Adams, which is only a day trip (+/- 12 hours), but I bought it for an Emmons climb on Mt Rainier coming up in a couple of weeks. I've done a number of day hikes with it too, leading up to these climbs. Its very comfortable and distributes the weight well, even when not very full (I've been training with 40-45lbs). The top pouch doesn't sit very tightly when the pack is not very full (even with the staps are pulled to their max on it), so it bounces around a bit. Also, though there are holes on both sides for the straw on a bladder to poke through, there's no little straps on the shoulder harness to keep it close. Its been relatively easy to swing my arm around to grab it (like looking for your octopus in scuba diving), but it would be nice to have it more accessible. Otherwise its awesome!