Eight months with one supplier, then a change in how they communicate that I noticed before I noticed anything about the product.
Posting the whole record, including the parts that do not flatter my decision.
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 flattering data point from a group buy is not consistency. Consistency means separate batches, separately commissioned, over months.
The bit I cannot resolve on my own is what a vetting checklist should actually contain, as opposed to a list of things that are easy to fake. Happy to be told the question itself is wrong.
PharmHunterJen said:Eight months with one supplier, then a change in how they communicate that I noticed before I noticed anything about the product.
PharmHunterJen has the substance of this right. The condition it depends on is worth stating. 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.
PharmHunterJen 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 StandardsTaking the question as asked, rather than the general version of it. The useful checklist is about verifiability rather than presentation. Independent test results commissioned by buyers rather than by the seller, consistency across multiple batches over time rather than one flattering report, a physical address and a company registration that resolve, batch and lot numbers on the actual labelling, and a shipping practice that matches what the material needs. Everything a good-looking website provides is cheap to fake; none of the items above are.
LabKate said:The pattern that distinguishes a bad batch from an exit is behaviour rather than product.
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.
Correct me if the detail matters more than I have assumed.