Very few plugins can warp vocals as well as this does. This isn't meant to be a pitch correction plugin that leaves your pretty little vocal otherwise unscathed. Think of it more as a vocoder on steroids. If you are looking for pitch correction, get Melodyne. It's the best. If you are looking for vocal robotics, mind-warping midi-controlled pitch, formant and other changes, this is one of the best plugins out. I've been very happy with it, though I have no illusions about what it is appropriate for. If you're looking for Autotune, move along.
PS: Polyverse put out a couple nice tutorials as well, to break us out of a mental box.