Last weekend I went to the Cannabis expo at the Cow Palace in San Francisco. A pretty interesting and big event attended by 15000 people in total. One thing that got my attention was the so called vapor pen. You cannot put herb in it but a liquid formula that is being sold at some dispensaries in the LA area. The "vapor" looked more like a mist to me, yet I was intrigued especially with the stealth of this device. Didn't buy one though as the liquid extract is not (yet?) available in dispensaries in San Francisco. Has anyone here tried this device and if so what's your experience?