I've only been vaping (this time around) for a week, but in that whole time I've had a maximum of three cigs per day.
Went swimming this afternoon, and while I'm still seriously unfit(!) I'm pretty sure those lengths felt easier than before.
I seem to have more of a sense of smell already as well.
So, what I'm asking is - how soon did you start to feel "health benefits" and what were they?