I have the smallest and largest keepalls (the largest one with a strap), as well as the Eole. I traveled with the largest keepall before the Eole came out. Once it did, I bought it immediately! I usually pack so much to carryon with me on the plane that the Eole with wheels was so much more convenient for me. Before, with the keepall, it was loaded with stuff and super heavy to carry. There wass never an issue with it being a carry on (that is, i am pretty sure that it does fit the requirements). I haven't used my keepall in years, but use the Eole all the time! It fits the dimensions for a carryon for a large aircraft. I have only had to check it on if I was flying on a super small airplane (like a puddle jumper, from one Carribbean island to another). I love the Eole and it comes with me on all my travels! Hope this helps, and good luck!