I am using a 570 oz. stepper to drive the Z axis on my PM 25MV mill. This is a tough job, the mill has some places that take extra torque to move the heavy mill head. This motor handles the job well except when it is stopped in one of these locations and if I have to speed turned up too high it can't start moving the load before it gets a command for the next step. I just turn down the speed a little and all is well. I going to use another one for the X axis. Not going CNC for now, I just don't want to do all that cranking so letting a motor do it.