Eight months with one supplier, then a change in how they communicate that I noticed before I noticed anything about the product.
Writing it up rather than posting a verdict, because a verdict is not checkable and the detail is.
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.
A caveat about community reputation: it is a lagging indicator. Reports arrive weeks after orders, so a supplier can look excellent for a month after quality has already changed.
What would genuinely help is knowing what a vetting checklist should actually contain, as opposed to a list of things that are easy to fake. I have searched first, so if this is covered somewhere point me at it and I will read it.
SteveThurs 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 SteveThurs. One condition attached. 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.
SteveThurs 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 StandardsShort answer first, then the reasoning. 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.