Internally, I'm around 16, maybe as old as 23. According to my birth certificate, I'm in my 40's, and yet I still get carded (and love it).
I'm thinking of all the people on this thread, I have the smallest devices. I've been with V2 batts since 2011 and while I've had plenty of opportunity to go to bigger, probably better, devices I choose not to. I've been given mods and then gave them away, as I do prefer the cig-a-like for many reasons, but near the top is that in public, they are very easy to use. I vape everywhere with respect.
A few weeks, while golfing, there was another vaper there using his big device. I said to him, "you call that a vape device?" and then pulled out my cigalike and said, "this is a vape device!" Obviously, I was just having fun with him and knew he'd be all bragging about his bigger device. But I don't really care what fellow vapers in the wild use. My thought is use what works for you and whatever you spent money on to enjoy the same activity.
I also really like that my devices never put me over the 3 ml in a day category, and am usually at 1ml to 2 daily. I'm thinking on a bigger device that is enough for an hour, and yet, I vape probably as many puffs as most die hard vapers in a day.