I'm not defending their claims. I'm just asking, and I really do think that could be useful to have some study on that. Studies on vaporized marijuana says that are some benefits of that form of application: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4456813/ While not having any research paper to deny nor support thesis about health benefits of vaporizing other herbs it's hard to have strong opinion on that. It's probably safer to avoid it - as you said - not being guinea pig, until there's some paper published.