The only study i will ever quote in my life at the moment is the study done by the UK royal college of physicians that said vaping is 95% safter than smoking. the problem with alot of studies saying how "this chemical was found its bad" that have been done in the past was that the fluid they used, the power level, the device how long it was fired for, etc... are so dynamic that it's not conclusive.
Honestly, I treat it like smoking, do you current smoke? if not, i probably wouldn't vape. Do you smoke and want to quit or want to replace it with something else? then try a vape. Actually, Here in Canada, we were very strongly against selling e cigarettes to people who were not smokers (not saying we denied them service) because the message we were trying to get across was that this was a tool to reduce harm from tobacco. I have been vaping for 10 years now, and if i was not vaping, i would be smoking about a pack of cigarettes a day. some people have their vices in life, i don't drink, i just enjoy nicotine.
We don't get many of these signs around where i live to buy a flipper.