All of the Chinese vendors have issues, some more frequently than others, and many just disappear after their failures. I know a lot of people who have had issues with QSC, and I totally understand that many people don't want anything to do with them. I'm fortunate that I've never had a problem, but I operate under the eyes-wide-open policy of it's not a matter of if a Chinese supplier will fail me but when.
We're not buying vitamins from Amazon, and anyone expecting Amazon-level customer service, hand-holding, or refund/return policies may be better off sticking with big pharma products. Everyone needs to approach this hobby understanding that we're still doing business with high-tech drug dealers, and in the end it's really not very different than buying crack from guys out on the street except the Chinese aren't going to break your legs.