I brought this pack on a 4-month tour of South America and it did not disappoint. For the price, the Ruckpack is an exceptional travel backpack, the 40-liter capacity is the perfect carry-on size with enough space for all your gear. I had no trouble at all carrying-on with even the cheapest budget airlines (I'm looking at you, Fly Bondi). The full-zip main compartment makes unpacking a breeze, while the side and top zippered pockets offer plenty of room for travel documents and loose items. The internal hydration slip easily doubles as a laptop compartment and a stowable rain fly gives you piece of mind when traveling in bad weather, or as extra security when in sketchy areas.
While I wouldn't bring this pack on a multi-day backpacking trip, its padded shoulder straps and burly waist belt offer plenty of comfort for a long weekend trip or as a carry-on pack for a multi-month overseas journey.
The only shortcoming of this pack is in the main compartment zipper design. Because of the full-zip design, you are unable to fully pack the compartment while it's laying flat. After a few days of trial and error I found a simple remedy by zipping it up 2/3 of the way, then setting the pack upright to loading it completely.