Popular unit colors? Tan comes to mind. And many do have red tips. And yes, I do have a dirty mind. ;-)
Yeah, tan "filter" with white battery kind of looks like a cig. But who are you trying to fool? I remember well the first choice I made, trying to minimize my embarrassment to be seen with this weird novelty gadget, hoping it would pass for a real cigarette if anyone saw me. And I knew I'd feel stupid sucking on something that looked like a pen or a marker, or worse, like some kind of dope pipe. And it's a legitimate concern to the novice vaper. So I am sympathetic to it. But I will advise all newbies... this will pass. You will spend a hundred or two on cigarette-looking vaporizers, and you will move up to something better. It's a rite of passage. There are many here who will try to get you to jump straight ahead to the latest and greatest.
They mean well. But I must make this comparison. Speaking as an older guy, I remember, looking back, that sex was much better with experienced women than with my high school sweetheart, but would you advise your teenage son to skip the girls his age and jump straight to cougars? I didn't think so.
