I've had a package from eHobby Asia sitting in customs since Sunday, which is unusually long for anything I order. I hope they're not picking my battery packs apart to make sure there's nothing illegal inside them. That would suck.
On the topic of my mags, the only reason I could think of that they would pick every mag apart is if they were actually looking for drugs or some other contraband being smuggled inside the mags. I can't imagine a customs officer would be stupid enough to have to take all 4 mags apart to make sure they were really airsoft mags.