"Simply buy several and remain near your gear with a fire extinguisher for a day or two just to be safe"
This is actionable behavior in a court of law. It is DEFAMATION.
So is claiming a mains fuse is directional, and also dangerous to tell non techs to keep reversing them, until one time they forget to disconnect the plug from the mains, BANG!!! say goodbye to your short and curlies.
Cheers George