From what I've read around here, most of the authorities seem to be very aware of these types of devices, and don't offer too much of a problem. I live in a small midwestern area, and most of my problem occurs in the small towns, where people simply have never seen anything like one of those things. Strangely enough, the weirder it looks, the quicker they accept it and leave you alone. I have to explain away my ego a lot quicker than when they see a box mod with a voltmeter glaring at them.