My main carry on is a backpack/bookbag made by REI...I think its a great carryon- I have a 15" laptop as well, I put that into a flexible foa4UWm shell made by Case Logic and put that into the main compartment and it fits fine...I have tons of room for other stuff too...Im not a huge fan of rollaboards so the backpack is a perfect solution for me...and even fully loaded I can usually get it under a coach seat...
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