What motion device are you using with Mach3/Mach4? I have an older SIEG KX3CNC with a Ethernet Smooth Stepper and a simple breakout board. It has performed well on that little machine. I Got hold of a Bridgeport Boss with a dead control with the intention of tearing he old control out and replacing it with as Ethernet Smooth Stepper and a newer breakout board. Was progressing along and shorted a ground to and input pin and when i next checked the ESS board was completely dead. Yes, I should not have shorted that, however briefly, but having worked with industrial controls and CNC machine for most of my adult life I did not expect the ESS to be destroyed and the breakout board to be fairly unscathed...
And then there is the problem that the ESS seems to be an orphan product now... Responce times were not the greatest back when i purchased it, but hey, life happens (I wound up in the hospital for 45 days a year ago under such cirumstances) and now it seems that the SmoothStepper site is pretty much stagnant.
What products are others using, what issues do you have with reliability, support and overall performance? I know there are those that have their issues with Mach3/4 but I have have very good results using Mach3 in a light production environment. The issue that I am now having is the hardware.