it seems there are a lot of upset writers on here but personally I thought it was an amazing movie, there is one thing I agree on tho it did feel like it kept speeding up the pace but it's a movie so at least to me it makes sense they have a designated time slot to fill with the story, and I feel that they did the best with the time they had available. I think most people go into this with the memory of the more well-paced 2nd season but that's a flawed way of looking at it, it's not a season, it's a movie. with all that said the animation was absolutely stunning and seemed like they may have been paid more for this one.
If you're a fan absolutely watch, if you're not a fan go watch the main show first, and if you don't like the show... well I don't know what to say to that...