solid pack. it looks like a big turtle shell that sticks off your back,,, but it is a quality bag that packs well and is carry on size OK. never had an issue with any of the flights. this packs well and is easy to access once you are in your hostel or destination. I had traveled before with my internal framed top loading backpacking pack. I love it too. I think if i was going to be putting serious miles on my feet, i still would take my top loading backpacking pack. I have more comfortable packs for hauling weight around a town or backcountry for any considerable time. this one is great for civilized travel - as it is intended. This one is built very well tho. it uses very thick and durable fabriv, zippers, etc. it will last forever. i almost prefer a more minimally designed pack, but with a better load carrying frame. I would just have to use stuff sacks or packing cubes with a top loader as opposed to this panel loader.