I've been looking down this road as well. My logic being that e-cigs/e-juice could be become scarce commodities at any time, so an alternative would be a good idea.
After checking some reviews and how-to videos, I picked up an Iolite.
The Iolite seems to get too hot for e-liquid. Dripping straight into the <ahem> 'legal herb chamber' produces what seems to me like airborne plasma. Flavors are distorted and hot hot hot.
So I tried putting in polyfill and dripping on that. Again waaaay too hot. Looked like the polyfill fused with some aspect of the eliquid and turned solid.
So I tried with half of a cotton ball. Still burn your nose off hot.
With all forms of dripping, holding the draw in your mouth for a couple seconds cools it enough to inhale safely, but the taste is still badly distorted.
With that, I've concluded that e-cigs run a lot cooler than the 395F temp of an herbal vaporizer. E-cigs are also MUCH easier to deal with.
Sooo, I got some pipe tobacco, shoved a pinch into the bowl and it works pretty well. It provides VERY little visible vapor, but such a powerful flavor that it satisfies. Trouble is, it tastes more like pipe tobacco than pipe tobacco smells. Very dominant aroma that sticks in a room almost like smoke. Nicotine is definitly present but the taste is a little too pipey for me.
Shisha tobacco. This is tobacco that has been soaked in glycerin with flavors added. This stuff is incredibly sticky and messy. I make an aluminum foil 'cup' or 'crucible' and place it in the upper bowl half. It produces light visible vapor for quite a while. Zero throat hit, but VERY good flavor. The flavor only lasts about 5-10 minutes. After that it continues to make vapor, it just has no flavor, or starts tasting kind of rancid. Trouble is, all that sticky stuff turns into thick black tar. If it escapes the aluminum foil, it turns the bowl black. This stuff has to be scrubbed with alcohol to remove. As it accumulates, it begins making foul vapor, so fairly frequent cleaning is required.
Overall, the hookah-shisha tobacco offers tastiness at least on par with e-cigs. I tried Starbuzz Blue Mist, Chocolate Mint, and Cappucino. All three were quite good, especially the Blue Mist. On the downside, cleaning the Iolite bowl is not easy. Loading and even removing the little aluminum foil crucibles is messy and annoying.
Right now I'm debating whether to get a full blown desktop vaporizer with a large open bowl (about $200). This is a matter for debate, because it might be smarter to just get a hookah pipe (water ....), as they're much cheaper than vaporizers (hookah-shisha.com will give you one for free with $100 purchase), and if used correctly, they're almost as clean.
So that's where I'm at. Desktop vaporizers allow the user to control the temperature, which would 'theoretically' allow you to dial-in the perfect temperature for e-juice, as well as deploy shisha at a whim.
Is anyone able to relate experience with both ejuice and shisha on an herbal vaporizer????