Get Surfaced!!!
I don't actually own Dangerous, but several people I know do, and I was was watching a really old vhs with Dai Vernon on it the other day and he was saying how he only liked to perfform the most difficult effects, he didn't want something everybody else could do.
To sum it up, if you are the typical, theory11/ellusionist fanboy, practice as little as possible but still want to perform a lot magician, go ahead and buy Dangerous, if you want to actually learn some advanced, difficult sleights that will advance your magic greatly if you put it to good use, buy Surfaced, the tricks are amazing. There's a reverse-elevator type trick on it as well, and it's pretty awesome. (lots of other stuff too)