The Raven is one of those effects that you either love or hate. There is a DVD etc... that is available that shows you lots of posibilities with it.
However there are lots of things to think about before you purchase one.
Are you willing to carry it around all the time?
Do you wear the right kind of clothing to support wearing a p***???
What kind of effects will you use it for? and can you accomplish it another way?
I owned the Raven and the DVD for about 5 years, then I suddenly woke up one day and took a disliking to it. My suggestion is, forget the Raven and learn those types of effects using sleight of hand.
Scotty