Opinions are varied. I think most people thing it is "disappointing" more than "bad" - like it could have been better, especially (as noted) given the amount of money it cost to build.
At least for the MK, though, I think it serves a good role of being a high capacity people eater but not star attraction in Fantasyland which needed it. To me, it's better quality than the smaller older dark rides, though not as "quaint". The AAs aren't anything special, but they are better than the cardboard flats of smaller rides and the music and scenes are enjoyable enough. But it really suffers from being a very paint by the numbers "book report" of the movie and also has a rushed ending. In MK, it also has a very elaborate queue that seems to indicate that the ride will be bigger/better than it is, so it creates more of a setup to be let down.