Answering 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.
Eight months with one supplier, then a change in how they communicate that I noticed before I noticed anything about the product.
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.
What I am after is 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.
Dr.MetabolicMD 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.
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Shop Reference Standardsbbq_ray_KC said:Eight months with one supplier, then a change in how they communicate that I noticed before I noticed anything about the product.
This matches mine closely enough to be worth saying so. 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.
Happy to go further on any of that.
Adding the clinical framing, because it changes how the question reads.
Vendor reputation tracking for vendor vetting: I maintain a personal spreadsheet with every order I've placed — date, vendor, batch number, Janoshik result, personal efficacy assessment (1-5 scale), and any issues.
After 20 orders across 5 vendors: average purity 97.4%, zero sterility concerns, 0 shipping issues (all resolved). This data gives me confidence in my current source and documentation if issues arise.
I encourage everyone to track their orders systematically. Community data aggregation makes us all safer.