This is where the dealer comes into account.
If you choose crefully your dealer, he will either provide quality control (think TTK) or after sales service if you received a defective watch (happend once with King, she send another one right away).
This can explain the price difference between dealers, not to mention delays (TTK for example does an intensive QC on his watch, so there's no way you'll get it in a few days).
QC is typicaly a dealer problem (I remember a thread on the subject telling with dealer did a QC and witch did not...)