F here. (I really think there are many more still-smoker-vapers within and beyond ECF than these threads suggest.)
I've been
vaping since January 2010. I've smoked for well over 40 years, at peak 1.5 PAD--so just a heavy-ish smoker. My goal has never been to quit entirely, and I'm not one of those people who immediately found the taste of cigarettes repulsive. I still love smoking and the smell of smoke. But for more than a year and a half, I've been very strict about keeping it down to no more than four Marlboro 100s a day-- two right when I get up in the morning and two late at night, maximum. The temptation to allow myself a heavy-smoking day doesn't come up, so I figure I'm at a good equilibrium place with this plan. (Plus, I choose to think those four cigarettes are health neutral in the larger scheme of things.)
Besides feeling and breathing considerably better, one thing that has changed is what happens when I run out of cigarettes. I now buy two packs at a time (about every 10 days) instead of a carton. Used to be that being down to two packs meant it was time to buy a carton. Several times lately, I've forgotten I was running out, even to the point of not having two tomorrow-morning cigarettes and just said "Oh well... I'll vape instead," without any panic.
During my smoke-free daytimes, I vape about 4-5ml a day of 20mg.