The best piece of Briggs& Riley luggage I use (am using it now), is the Baseline Expandable Carry-on. It expands really well and fits under most all seats, definitely overhead storage. I can travel a week with that alone, the way I pack. I'm actually thinking about buying another one just in case they stop making them. The shoulder strap is the best for comfort walking long distances.

https://www.briggs-riley.com/product...cabin-bag-231x

It travels slim or larger based on all the expandable zippers to adjust the size. Has a slip in sleeve to attach to a roller board.