i saw it last week and loved it, I went prepared for dark psychotic characters since requiem for a dream, still I closed my eyes in some scenes like the Ryder last one for example.

I think Aronofsky is a genious, since the π movie i have loved him, his direction is so fast and all this play with mirrors and mind games, he can transfer deep emotions into an image, when i left the cinema I didnt know what was real ad what not.

Portman and Kunis were amazin and I liked Vincent Cassel role a lot!

about portman doubles from wiki
For certain scenes, American Ballet Theatre soloists Sarah Lane and Maria Riccetto were "dance doubles" for Portman and Kunis respectively.[12] At other times, Kimberly Prosa serves as the body double for Portman.[13] Aronofsky said during filming about Portman's ballet performance, "She was able to pull it off. Except for the wide shots when she has to be en pointe for a real long time, it's Natalie on screen. I haven't used her double a lot."