If you get seized you get seized, it won't make any difference how large your order was. The "Personal Use" exemption applies ONLY to meds you personally carry across the border from Canada or Mexico or wherever. You cannot "assign" the right to carry your meds to a third party (IOP).

This is a very big "grey area" as you say.

If a small quantity of Valium gets seized by customs, chances are all that will happen is you will get a customs "love" letter.

But if you use the so called "Domestic Option" then there should be no customs risk at all. Isn't that what you pay extra for?