Flagging this early and with the caveat that I may be wrong about part of it. I would rather be corrected than quiet.
Eight months with one supplier, then a change in how they communicate that I noticed before I noticed anything about the product.
One flattering data point from a group buy is not consistency. Consistency means separate batches, separately commissioned, over months.
What to check: 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.
If your experience contradicts this, say so in the thread — I would rather be corrected here than have people act on a warning that does not hold.
COA_Karl said:Eight months with one supplier, then a change in how they communicate that I noticed before I noticed anything about the product.
No disagreement with COA_Karl. One condition attached. Prices dramatically below market are the strongest single signal, and the reason is arithmetic rather than suspicion. Synthesis, testing, and cold-chain shipping have floors. A price well under the floor means something was skipped, and the two things that get skipped are testing and content.
COA_Karl said:Eight months with one supplier, then a change in how they communicate that I noticed before I noticed anything about the product.
I disagree that testing history is decisive. It tells you what a supplier did when they were being watched. Continuity of behaviour under stress — a late shipment, a failed test, a complaint — is more predictive than any run of good results.
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Shop Reference StandardsAnswering the narrow version, because the broad one does not have a single answer. 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.
Dr.BariatricHTX said:Prices dramatically below market are the strongest single signal, and the reason is arithmetic rather than suspicion.
Same position here, arrived at the long way round. One addition: an unstated method makes a report close to uninterpretable. "99% pure" without the technique, the standard and the conditions is a claim, not a measurement.