I have the RS 21" rolling carryon. We had another one, the 22", for about 14 years until the zipper gave up, so last year had to replace it. I know this bag isn't overly exciting, but I love it. It is not that heavy, expands nicely, and does well on cobblestones. I can fit so much into it when I need;) The quality is there as well.
Last month I brought some cookware home in it. My trip was only overnight, so I had minimal toiletries, a quick change of clothes and a nightgown. I still managed to pack a soup pot, a large 12" skillet with a long handle, a large saucepan and all the lids. The handle from the skillet really pushed the limits and it was a bit tough to get the zipper just right to close, but I did it. When I unpacked, the bag looked no worse for the wear.