Just beware that with airlines cramming more seats into their planes a bag this size will crowd the area that your feet want to habitat. I've done it with my REI Overnighter but wouldn't recommend it since being able to stretch your legs out makes a big difference in comfort. BTW, unless you're using the Western Flyer more like a laptop bag I'd get the Tri-Star. You can underpack it when you don't need the space or take it along on 2-3 day business trips if you know how pack light (and leave the wheeled bag at home.)