Well, I think the studies quite clearly show that an electronic cigarette.... Now, you're talking about two different products: an electronic cigarette and a tank system are two different things, but they both produce vapour. I think all the studies show that they are vastly superior to traditional cigarettes as far as harm reduction goes.
Nicotine in and of itself doesn't really cause too much harm in comparison. There are increased rates for potential heart attack, but much less than those from traditional cigarettes, and you don't have the 3,000-plus carcinogens that a traditional tobacco stick has. I think there's no question that they are far safer. I guess that would be my answer to that.