In short: it was great. One of the best video game adaptations ever. Waaaay better than the P4 anime(and P4 is my favorite game). Unlike the P4 anime, the fights are actually decent in this. It also sticks to the story more, and doesn't feel rushed or toned down.
On a side note: I love what they did with the main character. Makoto actually gets great character development in the movie. Thus, I prefer him to his game counter part.
Persona was always going to be hard to adapt into an anime, but P3 seems to have hit a sweet spot. Can't wait for the sequel. Hopefully, the P4: Golden anime is done more like this.