Answering the narrow version, because the broad one does not have a single answer. 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.
Eight months with one supplier, then a change in how they communicate that I noticed before I noticed anything about the product.
So the question, as narrowly as I can put it: what a vetting checklist should actually contain, as opposed to a list of things that are easy to fake.
If the honest answer is that nobody knows, that is a useful answer and I would rather have it.
Dr.RaviCardio said:The useful checklist is about verifiability rather than presentation.
Agreed, with 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.
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Shop Reference Standardsstefan_berlin 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. 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.
Clinical perspective, offered as context rather than as advice.
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 14 orders across 5 vendors: average purity 97.6%, 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.