I have both types and even non-wheel duffle bags. It depends on the the type of trip. Pelicans with two wheels used for certain long term trips. Briggs &Riley spinners for other trips and Rimowa spinner for short trips. Duffles for certain countries and long stays. They all serve a a different purpose. The thing I don't like about spinners is that the wheels could get damaged more easily, and the fact they can get uncontrollable in some situations. Two wheelers are more controllable and the wheels are more stable. Duffle bags and backpacks are the best for maneuverability. So, it all depends.