Wow! That's shocking! I've just ordered a machine (6090B) from Jinan J-Cut that's being assembled this week for shipping soon, and hope maybe this is a different seller to the one you guys have dealt with?
I've been dealing with Shanny there over the last week who has been extremely helpful with photos and my many, many requests for more info on the parts and specs. There seems to be a whole district or province with similar names, models, and machines?
The one issue I wasn't happy with I would say is that there is a real lack of info on the web for all these types of Chinese CNC's, as to the hardware and software configuration, and specs, hence my annoying poor Shanny with heaps of emails, but it is good to know the model steppers, drivers, etc, etc. I plan to comprehensively document and photo the entire process and take massive amounts of photos along the way, along with all the machine details, and put them up to help others.
Have there been others with problems too? What were they, and what was the end results?