I would avoid belt drive, extra complexity is extra problems. They will also limit the maximum speed of the machine if you look at my convertion or the hoss machine you would be better to follow that template. The g540 is the way to go i have used some of the drives from the uk and they are not a patch on this setup. Keling was where i go my drive and motors from.

http://www.cnczone.com/forums/bencht...g_machine.html