Brought the 28" duffel bags on our two week Italy trip. Worked fantastic. light and super easy to take around the cities and between train stations.
I especially enjoyed how it fit in the overhead bins of the trains and I did not have to store them at the end of the carriage to be rummaged through by pickpockets [this seriously happened on our car, conductor came through with security and escorted a guy out for stealing].
My only complaint is that it does not stand up on its own vertically, you have to lay it down. But that TBH is a very common complaint for soft duffel bags.