Hi, I'm looking for a better (more intuitive) way to adjust the volumes and add effects to stems on my S3 controller. I am thinking of using a second hand F1. Hopefully I can use this to control stems on 2 decks. But second hand gear is a little concerning, not knowing the history of a unit is a worry. Some folks say they are very rugged, and others say they have been broken. I cannot find another NI midi controller with 4 sliders, to use as stem volumes. I have been told the Allen & Heath Xone K3 needs to be mapped to Traktor, and there is no mapping from A&H. Please does anyone have a suggestion, or comment. By the way I'm a 70+ years young, open format (Soul, Funk, Reggae, Rare Groove, World) DJ.