Overseas chinese stuff can be hit and miss. Sometimes this happens. But when judging retailers you really have to look at how they handle a problem once it happens - communications, speed of response to your problem, willingness to refund or replace, etc. On that basis one can make a judgement.
I would not make excuses for retailers on the basis of volume or poor comms - those things are ENTIRELY within their control. But drop shipped chinasoft stuff on the cheap, you can't expect the world of. Adjust your expectations of that stuff but hold the retailer accountable for his actions for sure.