Sometimes a hard-sided carry-on bag is just the ticket. Delsey has a winner with the Helium Aero 19-inch International Carry-On Expandable Trolley, which is loaded with useful features not common in most wheel-aboards.
The 19-by-13-by-9 1/2-inch polycarbonate bag is tough but lightweight. It expands 2 inches in depth thanks to an external zipper. A spacious front zippered compartment with a built-in padded sleeve and two big zippered mesh pockets open partway to keep files, a laptop and accessories secure. Or you can snap out the side panels to open fully for maximum access.
The bag rolls on four 360-degree-rotation twin spinner wheels and has a recessed pull-handle system as well as top and side padded handles. You can use the built-in TSA-compliant combination lock or the dual zippers can be secured with a device of your choosing.
Delsey Helium Aero 19-inch International Carry-On Expandable Trolley is about $150 at luggage stores and online.