Dr.PulmRoch said:

The pattern that distinguishes a bad batch from an exit is behaviour rather than product.

Genuinely useful, thank you. I had the facts and not the framework. Printing the relevant bit and taking it with me.

Clinical perspective, offered as context rather than as advice. Worth answering the question that was asked rather than the one behind it. The narrow version usually has an answer; the broad version usually does not, and answering the broad one is how a thread stops being useful.

Dr.RenalNash said:

Vendor reputation tracking for vendor vetting: I maintain a personal spreadsheet with every order I've placed — date, vendor, batch number, Janoshik…

I read this differently from Dr.RenalNash, on substance rather than tone. Filing an objection on the n=1 problem. Personal experience is genuine evidence about one person and very weak evidence about anybody else, and this thread keeps promoting the first into the second.

The figures, for anyone assembling their own picture. For anyone reading later: the numbers in this thread are worth checking against a primary source before you act on them, including mine. Half the figures circulating in this community trace back to a secondary summary that dropped a qualifier.

I would rather be corrected than agreed with, if it comes to it.

Moderator note: reminder that nothing in this thread is medical advice, and that clinical claims need a source.