Recently returned from 3 weeks in Mongolia and my Nest backpack performed like a rockstar on its first trip! My adventure did not go easy on this bag - it was overpacked, rained and hailed on, left in the dirt and tossed around in Russian off road vans. This bag took all the punishment and came out looking like a polished civilized commuter backpack when it was time to head home - very impressive. Why four stars and not five? A couple of minor adjustments would make this bag perfect: The passover sleeve needs to be more rigid as it is crumples when you go to put over the handle of the wheeled carry on. The outside side pocket needs to be bigger/expand more to fit a life sized water bottle as in at least 32 oz. Overall an amazing backpack especially when paired with the wheeled carryon.