We do not allow source discussion so I am going to close this. I will leave you with this idea it is possible and probable that Chinese vendors will have multiple websites. It is also likely that vendors get products from similar labs as realistically there can not be a huge number of labs producing RCs. I may be wrong but as its a specialized sale and its a constantly changing market the only people who will take the risks have the infrastructure to do so. This makes start up hard means that there will inherently be less people fulfilling the demand as those doing it are already satisfactory.
This is closed as source/vendor discussion.