ARE YOU WATCHING CLOSELY? Yes, The Prestige is worth seeing, although your level of enjoyment may drop as you reach the end of the film, described accurately (I think) by Tony Scott as "an element of bunk that compromises the coherence of the film’s concept".
Which is not to say that it's not an interesting way to wrap things up, only that it makes the movie something which it wasn't been before. And I say this as someone who deduced the Christian Bale-related twist from early in the film but enjoyed the heck out of most of it anyway. Beyond that, it's all spoilers.