Visual guide: https://www.supergreenlab.com/guide/how-to-build-a-ikea-eket...
I’m not sure I believe the carbon filter reduces the smell to nothing, in my experience it still stinks while running through an internal AND external carbon filter.
If someone smokes a joint near your window, that smell will probably be gone in half an hour. If there is a plant that's just sitting there, it'll be more subtle, but it's not going anywhere.
That said – many people like the smell of Hopfentee (Hop tea), which is pretty similar.
Is there higher risk of infection transmission? I'm sure those reports a few years ago of serious lung infections from tainted vape oils are biasing my thinking here, but it also makes some sense that a high-temperature flame on a dry medium wouldn't transmit nearly as many microorganisms as a lower temperature vaporization of a wet medium.