I have always stuck with a handful of companies..
Jarrow
Doctor's Best
Life Extension
TN
BioAstin
and Now Foods (rarely but sometimes)
Don't get me wrong there are intriguing products with 4 to 20 ingredients in them that look great on paper but you have to worry about their sourcing department finding the right species(etc) from the vendor(and they are shopping for the cheapest price), testing done to ensure identity and purity of the material, correct processing and encapsulation or mixing without contamination or incorrectly blended ratios, and finally testing ($$$) to ensure all the ingredients on the label meet the claim(if they even bother with this). There is a lot better chance the companies I mentioned above have the resources, expertise and experience, and money to foot the bill for ALL of that than some current or former bodybuilder or influencer trying to run a business and still make a buck.
I have personally seen a lot more claimed material failing testing in the last 6 months or so and I believe that stems from the supply chain and China/foreign raws.