I buy a lot online, and also in China. I have some favourite stores, and Gearbest is one of them. The reason I like them is that the have a lot of nice products on offer. Because I buy a lot, sometimes something goes wrong and I need the help of their helpdesk. Sometimes they can help me with technical advice, and sometimes that's not possible and I get a fair treatment, being a refund or a discount at a next purchase. Thas is important to me, because that gives confidence that they are here for the long run.
That is why I rate Gearbest with a 5 star rating. Not always the cheapest, but competitive.
If I have to give a point for improvement, that would be the carriers they sometimes select to send the stuff to Europe. If they select a bad carrier, the items takes months to arrive (or do not arrive at all, but then I get my money back). and selecting a track and trace option is not always the best choice if the products is cheap.