All the drama surrounding the dark net markets right now notwithstanding...
Can anyone comment as to whether it is a good or bad idea to order small amounts substances to a PO Box? I am mostly worried about safety - specifically about being put in cuffs when going to the post office to pick up a tiny aliquot of a plant that people have been using recreationally for thousands of years. Safer than ordering to home address? More dangerous? Are there any ways to make it safer?
Don't order to a P.O. box. You relinquish plausible deniability because you (usually) have to sign your name somewhere or supply some kind of ID to hold the right to that box to begin with.
At least with your own mailbox, no one can prove (as easily) that you intended to receive that mail. Anyone can flip through any phone book and send anyone mail at any time. A P.O. box is a bit more condemning.