I'm sure this backpack is well-made and will withstand the test of time, but the reason I bought it was the design. I wanted a travel backpack that would fit in the overhead but didn't leave me with just one change of clothes. This is like having a 60L pack on a budget 'carry-on only ticket.' When detached, the main 40L pack will fit in the overhead and the smaller pack will fit under my seat. As soon as I'm out of the airport I can reattach them and I have one 60L pack. Brilliant! It has lot of other great features too; the main ones that stand it apart from its competition is the supportive waist strap, hard case pocket for squishables, and the side handle to carry it like a bag. Thanks Thule.