I've brought the cnc 6040 and found a few issues with it and after a lot of frustration and a lot of help from peeps on here I think I've narrowed it down to 2 issues, one being the original psu was faulty and the other was my PC's on board LPT connection gave me missed steps (which I will confirm today once my LPT card arrives) the annoyance was that I checked the pc with another pc and it had the same issues but after reading this thread I think it was just sods law that the second one had the same issue which mislead me thinking the PC was fine.
but in the end I have upgraded the BoB + stepper motors + cables + PSU which has improved the performance greatly with 90% issues fixed but it seems the LPT setup is the main cause as previously mentioned in this thread as I have ran out of any other parts to replace
Once confirmed if it is the pc's onboard LPT connection causing the missed steps then for a beginner would the UC100 be enough for me?
Or would the UC400 still be advised (I only be using 3 motors for a while as being a beginner) so the UC300 would be wasted on me to my understanding.