Congratulations!
I made the transition to vaping after 35 years as a PAD smoker. That was over 2 years ago. And I love vaping!
As to demonstrations:
First of all, to my mind it is important to tell only those who want to know. Those who ask.
If you wish to demonstrate your vaping device to those nice people, it is easiest if you rehearse the demonstration in your mind beforehand. Or actually rehearse it at home. With the vaping gear in your hands. Make it fluent, make it sound easy, easy to understand.
(I myself am.. uhm.. technically challenged

And when I demonstrate an e-cig - and explain it in simple terms - then anybody can understand it. This stuff is not technical, this stuff is not scary, this stuff is not witchcraft. This stuff is really, really easy.

)
I do not know the mini Davide tanks. Perfect for demonstration purposes is an
IMIST atomizer . For the simple reason that you can take it apart in the middle and actually show the heating coil. You can even demonstrate the vaporizing process by dripping a little liquid on it and giving it a short (!!!) push on the battery button. Then it makes a little vapor. (Warning: a short push please, just until a little vapor forms, or you may burn out your atomizer

)
In my experience, a demonstration works best when it is held in very easy terms. We are speaking to laypeople. People who are not familiar with the concept at all.
Like "This is the battery. That supplies the power. When I push this button, it activates the battery. When the button is not pushed, no electricity flows. - This is the atomizer. That makes the vapor. It contains a heating coil, and when I activate the battery, the heating coil gets hot and vaporizes the liquid. . etc etc. "
It is also a good idea to read up on the ingredients of the liquid (propylene glycol, vegetable glycerine, destilled water, food flavoring and nicotine, if you want it. - I want it.

- 5 ingredients. Your hand has 5 fingers

) and that many of those ingredients are present in many household items such as toothpaste, and even in medical inhalers for those suffering from asthma (the propylene glycol).
To make a long story short:
I think it is a wonderful idea that you wish to give demonstrations to those who are interested.
This works best if you rehearse the demonstration beforehand. Until it is fluent, and very, very simple.
You gotta know the vaping gear that you are showing, and you gotta know what the liquids contain.
Oh, and if you wish to let smokers try the vaping gear (take a drag)
1. there are .. uhm..protectors to put over the mouth piece
2. a nice strong-tasting tobacco liquid mixed with caramel or vanilla works best. That mixture is delicious, it tastes like small sweet-flavored cigars. (Incidentally, I made the transition to vaping with exactly such a mixture). Smokers do not want to taste strawberry cheesecake, they usually want something that they can relate to.
And the best compliment you can get is "Wow! This is great! It feels just like smoking!" and "Wow! Do you sell those things? You know everything!

"
I wish you good success!
/edit:
Please remember to caution those who want to try a drag to fill their mouth with vapor first. And then inhale it -slowly and carefully. Very slowly and very carefully.

Tobacco cigarettes contain a substance that inhibits coughing. E-Liquid contains no such substance. (

)