Bro from my limited experience, a po box may be inclined to drawe customs to a package, a good source should pack well, tightly, compact, discreets packing, and a return addy on the reverse also helps I suggest, even if its fake, just use a fake delivery name, far safer than a po.box, in reality I know of little seizures of gear, perhaps 2 cases and they were small amounts of stuff, its also dependant on your area in usa, if your in NY then I think you gotta a greater chance of customs checking it etc.