So update on the Philly Zoo. system... I was carrying my P01 and a spare 19rd mag at the time. I ignored the system thinking "Im legal. The worst they can ask me is to go back to the car." Well, not a care in the world. I walked in like normal. Food for thought.... Also, not the first time I've walked through metal detectors in Philly while armed and have just been waved on. (Second was the little carnival in the summer under Penn's Landing) YMMV.