Every single postal package that comes into this country (Australia) is scanned. I imagine that there is more credibility if a package with supplements comes in from a company such as iHerb than from an individual.

I have not had any problem receiving Methycobalamin posted from iHerb but I do only get the one bottle of any particular supplement at any one time. There is import criteria and if ones abides by it then there is usually no problem.