Dr.ObesityMed said:

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

International shipping tracking for cross-border ordering orders: my experience with customs in the US when ordering from overseas:

Package cleared customs in 2 days, no issues.

Tips: always include a copy of your prescription, declare medication properly on customs forms, keep quantities reasonable (personal use = 3 month supply max), and use a vendor who has experience shipping to your country.

mike_mod said:

Right, and one flattering data point from a group buy is not consistency.

This is exactly what I could not find anywhere else. Adding it to my notes with a link back to this thread.

Dr.ObesityMed said:

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

One concrete data point for the thread. Say what you would expect to see if you were wrong, before you look. It is a small discipline and it changes what you notice.

Ask again with the specifics and you will get a better answer than this one.

Moderator note: good thread. Keeping it here rather than moving it, because the question is general enough to be useful. No action needed from anybody.