One word to answer your question... YES!
It's definitely worth it. I would have to say that its the best magic-related DVD I've bought in a while. The clipshift if such an amazing utility move. Like you've probably heard, there are virtually infinite uses for it. Now to answer your next question about it's difficulty. I think that its all a matter of opinion. I've heard people claim that they've mastered it in a week. Myself, I thought it was a particularly hard move to master. I think it took me about 2 months to perfect it. After one month, I could do the move practically flawlessly, but I still didn't like my Clipshift, so I practiced for another month, and now I would say that it looks as good as ever. Not Chad Nelson level, but pretty flawless. So yes, I would definitely recommend that you get Surfaced for Christmas.
-Gary-