One concrete data point for the thread. Red flags, in rough order of how much they should worry you: no verifiable address, no batch numbers, prices far under market, vendor-commissioned tests only, pressure toward irreversible payment, and shipping with no temperature control.
One thing that is still open after PharmacoVig_BOS’s answer:
How people are distinguishing a supplier having a bad batch from a supplier on the way out?
wendy_avl said:Red flags, in rough order of how much they should worry you: no verifiable address, no batch numbers, prices far under market, vendor-commissioned…
Coming at wendy_avl’s question from a different direction. The pattern that distinguishes a bad batch from an exit is behaviour rather than product. A bad batch comes with communication, a reshipment offer and a batch number. An exit comes with slower replies, pressure toward less reversible payment methods, sudden discounting, and the same reassurance repeated without any new information. The product tells you less than the correspondence does.
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Went back through my own correspondence with an earlier supplier and the warning signs were all there in the replies, weeks before the quality changed. I was reading the product and not the behaviour.
Dr.KarenChen said:The pattern that distinguishes a bad batch from an exit is behaviour rather than product.
Right, and one flattering data point from a group buy is not consistency. Consistency means separate batches, separately commissioned, over months.
That is the short version; the long version is somebody else's post.