Hi Ian, USBCNC is fantastic. i have been using it for about 6 months now and not a single problem with it, its super stable over ethernet thats what i would recommend doing if you have the CPU4 with ethernet! also if you have any problems or questions just e-mail bert who designed, built and wrote the software.

Also the software is just as easy to customise as Mach 3 in my opinion its a lot better then mach!

Thats my 2p worth

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