I am not in China, but I did just get back from vacation to Canada.
They use Epistar and some other brand perhaps the 5w chips are of another brand. I guess the 200 MOQ could only be shipped to 1 person but they said they would talk to their engineers about improving their lights although I've yet to hear back from them.
I am kinda believing that they are getting 1g/watt. While no one has completed a grow journal on rollitup there are plenty on other forums unless someone can show me wrong. Albeit, as discussed, I certainly don't think that makes it the "best" light.