I know quite a few of the factories and suppliers, some stuff I won't mention cause it's one factory or company talking crap about another...always 2 sides to a story. By the time TWS biz info comes out, it's usually super old, for the most part.
China factories can make nice boards, they are getting better & better every year. I have a friend who has a super small factory there & can make some really good boards that are quite complex constructions, then there are other factories that build boards that go to Big 5 for a reason. Bigger brands see boards that look good & are cheap, but going to China is a huge effort if you want a really good board...it's tough & frustrating, in the end everybody looks at margin. Europe is a piece of cake, they pretty much have everything dialed. US well most brands have their own factory, that's about the only way to do it. Every country can make great product & as you know can make crap...even the US.