Con: Just one. Please add a strap along the back of the bag to fit over the top of a luggage handle.
Pros: Oh, so many.
I travel quite a bit and have looked for over a year for a bag that would hold a lot but still fit under an airline seat. Wheeled under-seaters make no sense because the wheels & mechanism take up so much space, and often don't actually fit under the seat as promised. So I wanted a backpack that would leave me hands-free while negotiating airports and would give me easy access to contents while on the plane. And honestly, I also wanted it to look great. I have looked at and tried SO many bags.
I just had my first trip with this bag and it's perfect. In the main compartment, it held my computer, a stack of paperwork, two hard-drives, and other computer accessories. It also held my large toiletries bag, wallet and a few other items. In the top compartment I carried a pair of shoes, a heavy scarf, a t-shirt and another toiletries bag. In the two side pockets I put my travel documents, lipstick, some cash and credit cards, and few other things I wanted to access quickly while in the airport.
The bag was heavy with all of my stuff in it (although the bag itself is reasonably light-weight) but the wide padded shoulder straps made it very comfortable to carry. I adjusted the straps so the weight of the bag rested on the strongest part of my lower back. (Play with the adjustment to get what's comfortable for you.) I walked long concourses and to and from hotels…