Just got back from a trip to FL. After all the horror stories regarding taking scuba lights, etc in carry on I was pretty nervous about going through security with cannister lights, regs, etc.. I must say though I was pleasantly suprised, although at every checkpoint they swabbed the bag, I had no problems at all. Mostly just usual curiosity about the strange looking cannister thingys and why so many regulators hehe. Hopefully it's a sign that the folks at these checkpoints are getting used to divers coming through.