It's definitely better than the musicals, which I never really got my head around. But it is a shame that you are forced to do the movies first time around with rented Pokemon. It feels like going through the motions when what I really want to do is use my own choices. Surely picking the right pokemon with the appropriate moveset is the real challenge here?
I've yet to see a sidegame yet which is as good as the Pokeathlon in HeartGold/SoulSilver though. I spent ages with that!