Ex e cig user here. Pregnant with baby #2 so I've obviously quit... but I loved it. I had a range of vapes over the years, my big Smok one being the best (albeit stupidly expensive). In hindsight I was stupidly addicted and had it on my person at all times. I had a puff when I woke up, puffed as I got ready, puffed as I drove to work. Multiple puffs in work. Puffed when I drove home from work, puffed while watching tv, in bed, before I slept... quite bad isn't it 
But, I loved it. Especially menthol oils. I loved the feeling in your throat.
But, alas, I'm pregnant. Baby is more important than anything else. Still was one of my favourite self indulgent hobbies (much more so than drinking).
I smoked before that, albeit fairly casually. When I quit smoking because I jumped on the e cig bandwagon, I never missed it. I wouldn't have a drag now, nor would I start again as I have children. But they remind me of my uni and nightclub working days. When life was carefree. So I'll always think back on them fondly 