Not too big, not too small - perfect size for a day hike. I live in AZ and swear by the ventilated straps.  For me it helps.  My husband and I both have the same pack and it fits us both well.  It just looks a bit smaller on him, but appropriate in size not too small or feminine.  This does not come with a bladder, but it is compatible and a 3L bladder will fit.  Like everything we own made by Osprey, we love it.