I haven't tried the CSUSA DE head, but I do know from personal experience that the DE head that The Golden Nib sells will interchange with the CSUSA Mack 3 and Fusion.
Interesting. Those are the names of the controls for my CNC's. My laser is run on Mach 3 and my lathes have a Fusion control! I wonder if there are others in the works to be named after razors!