i'd say they're well worth the money. i've taught at several camps and i've seen quite a few people make real breakthroughs in their playing. i think the time away from "real world" issues (meals,jobs, families) and the company of like-minded folks plus the opportunity to ask instructors any questions you can think of allows people to reach levels of concentration that they don't regularly get to. of course, don't forget that you will have to put in your time and effort while you're there and try to carry some of the energy home with you to carry on your learning but i don't think the value of what you can gain from this kind of hands-on experience can be compared to videos and books. if you can afford the money and time i'd say give it a go.