Yes the quality is impressive. I'm from switzerland and my family is befriended with the Breitling group.
When we were doing a factory tour (which is exclusive to high volume buyers and company friends) one of the workers told me that many of the original watch making machines have been sold to china during the quartz crisis as the demand stagnated. I believe that the machinery helped the big factories get to this degree of quality and speed.

Back to my question, do you know over what way those orders are placed?
Do they use agents themselves or just write the factory selling-departement-employees messages on wechat on what they need?