I don't doubt the question of the risks. But I feel like 5 years is a good amount of time to know that I'm not in any more danger than I would be with cigarettes. There is of course the question of the liquid ingredients. But if you buy from a reputable seller you can be fairly certain that the ingredients are propylene glycol, vegetable glycerin, and artificial flavors. All of which have been studied for a long time. We know how they break down in the body and that they are relatively safe. That of course doesn't mean that ingestion via the lungs is just as safe as ingesting them via the stomach or intestines.

All that aside though, from my own experience I feel 400x better than I did while smoking, which is enough for me.

And on the note of building coils, it's basically that with a mechanical mod the only way to regulate the heat of the coils is by changing the resistance of the coils. The lower the resistance the hotter the vape. It also means there's less wires and electronics that would increase your resistance. Another important thing is that you can change the surface area that will be heating your liquid. That of course means more vapor! That's the basics of it anyway, as I understand them.

Edit: I didn't mention the danger of purposely short circuiting high discharge batteries to generate heat. That should be self explanatory. Well you aren't really short circuiting, but you can very easily get to that point if you don't know what you're doing. /responsible-adult-rant