Not directly for these products, however I usually buy only from sellers with feedback ratings above 99%, and check their negative feedback to see if there are any related to the product I'm going to buy. A great number of online vendors from China/HK sell counterfeit parts, also the best ones do that, sometimes unknowingly as they very often have no idea of what they sell, but those are ready made boards which is a completely different product. They could be spare parts for cheap old TVs (some have a analog only TV receiver on board). My experience with Far East sellers suggest to never ever buy active parts (chips, transistors) because they're very likely relabeled fake parts, while boards, modules and passives are usually ok. Probably not the best quality but they always worked.