Amazing experience seeing this movie in IMAX 3D. I kept ducking when things were flying towards the screen.
The movie itself was extremely engaging. It sucks you in and holds your attention right to the end. I didn't notice how long the movie was until close to the very end. There is no good time to take a bathroom break, so make sure you take care of business before the movie and go easy on the soda!
My only suggestion would be (this may sound silly, but I will do this next time I go go an IMAX movie) to bring something to pad the bridge of the IMAX glasses. My nose was hurting quite a bit by the end of the movie from the hard plastic of the glasses.