The movement speed for entities that are docked to rail turret axis blocks are different for mouse and joystick control.
the turning speed for mouse seems to be related to dps (increasing that on my mouse lets the entity rotate faster)
that makes the joystick only cool feeling ... but mostly useless. and might overly favorite higher dpi mice
when i set my old Logitech MX518 to 1600dpi and accelerated it rotates nearly twice as fast as i can archive while using the Joystick.
not that important for the game .. but if you could turn even faster with more dpi on your mouse you would maybe get an advantage.