Production grade CNC router Vs Homebuilt CNC router advice

[Voicecoil]

It's not that people don't want to help, in many cases it's down to not being in a position to give a full balanced view on a machine: to do that honestly & responsibly (i.e. not blabbing your mouth off) you'll need to have had a thorough examination of one "in the flesh", tested it for accuracy and actually used it for some real work. OK, it's fair to give an opinion on aspects of the design that normal engineering principles make obvious, but how the whole package performs can be a different thing.