I never researched the matter, and I forgot all my physics, so I can't tell what are the properties that make PG/VG better candidates, I only wanted to point out it's not the temperature. Not that it changes a thing ;-)

Just one little thing. I think this statement — "The liquid used is either propylene glycol or glycerine which vaporize at lower temperatures than water" — isn't quite accurate. If I remember correctly, water boild at about 100 degree Celsius, whereas PG boils at around 190 C and Glycerol vaporizes when heated to about 290 C.

Thanks in advance ;-)

Worth giving a try ;-)

"Please don’t let it cost over $349.99" -- looks like I'm late to sign the petition? ;-)