I used vaping to quit a 15 year smoking habit and it worked out but I ended up vaping on and off for like 10 years, I'm clear of nicotine products now though and feel a lot better, I still smoke a bunch of weed but I figure had to be one or the other and I made my choice

mint flavoring and certain pg/vg ratios are better.
my personal opinion: get a high quality vape ( like maybe xros 5 or variable power control if you can discipline yourself to extreme moderation )
but not perfectly healthy, when compared to no vapeing.
definitely under-researched. ( would yield ambiguous outcomes due to so many variable factors )