A friend of mine has built a dedicated laser-cutter-mill combo (opposite extreme of the MPCNC philosphy). He uses LinuxCNC to control that machine without any delay or other problems. He can cut vectors, engrave, burn raster images. He uses a 50 watts industry grade IR laser, not the simple chinese stuff, but something solid… Well, as a service engineer for a laser company, he as access to these toys.
Just to mention it…