I have a few Osprey packs - I have 2 50L packs (my bf has one, and I have one), a small 19L Flapjill, and this pack. All of them are great and super well made. This pack is large (31L) - I am able to use this under my seat as a "personal item" when I fly, but I'm able to stuff my laptop, large iPad, tons of camera gear (DSLR + 3 lenses), cables, and a book, and it still counts as a "small" backpack. It is very spacious, but also has nice compartments. I especially like the small one on the front, which perfectly fits my phone and another small item.