They are the high-end/legacy-end of hobby CNC.
The Grbl/Arduino stuff seems most prevalent/commonly sold.
That said, I was remiss in not mentioning LinuxCNC, &c., and as you note, they do have a more traditional G-code implementation w/ loops and variables and branches.
But, I don't think that this simulator supports all of that --- could someone post a sample program which does that sort of thing and test it?
