I'm going to sound really cynical here, & perhaps I am, but I would never collect this sort of thing because it seems like just another way of screwing even more money out of the fans. I like the books, because they are brilliant & make me laugh. My pleasure is in no way enhanced by these extras.
If I'd thought about it at the time though, I would have liked some teeth, because a) they were free (I think), and b) they were a genuine prop.