Heading to Vegas where rec is legal but use in public is not. I got a freebie CE4 510 threaded cheapie e-cig with a purchase that I have never used. I noticed that the dispensaries have pre-filled cartridges for sale and was wondering if anyone had any advice on whether that CE4 would be OK to use if I purchase a pre-filled cartridge or should I consider purchasing an e-cig rig when I get there? I like the idea of being able to stealth it up with an e-cig and since it was free I won't feel bad chucking it before coming home to my f'n illegal state. Any suggestions?