Hoss has a good write-up and spreadsheet here:
RF-45 Clone Mill
The prices and info are a bit out of date, but its a good starting point.
The best fit and finish for this type of machine is the rong fu brand, all others are lesser quality. I've heard the enco machine is near or at the bottom, though I don't have personal experience with it. I'm happy with my MTW, so far ... only had it a couple months though.