Have not mounted a cart on it yet because the Soundsmith knurled mounting screws that I used with the XYZ Universe are not long enough now that the arm is much thicker at the mount.
I experienced the same issue, though not with Soundsmith mounting screws. The 3D arm has a very thick headshell, and none of my mounting screws for a Ortofon cartridge were long enough. I ordered some more hardware, crisis averted.