I donno wtf Grump is talking about... the only BAD thing about it is the taste (super harsh, like your smoking shake) And the fact that you honestly have to smoke a GRIP of it to have any effects. When I say a grip I mean like between a quarter and half ounce depending on how your body reacts to it.
Basically I wouldnt ever spend money on it... but I dont regret trying it for free... the prices have came down ALOT at our local head shops (mainly because no-one smokes the shit) So it may be worth the $10-20 to try it for you.
If you do try it, go all out so you actually trip a bit off of it. OH YA it doesnt last very long AT ALL. 5-20 minutes tops.