I watched it twice and I loved it. But I read the book about 25 years ago and have wanted to see a live-action movie made of it ever since. I actually don't mind that the story is being stretched out to fill 3 movies, even though they could have easily told the entire story in one movie.
I also watched it in a regular theater and didn't get to see the 3D, 48 fps version. However, I've not heard too many good things about that. Mostly just about the framerate feeling too unnatural (even though the human eye sees at the equivalent of 60 fps). My theory is that people are just so accustomed to the 24 fps of movies and the 29.97 fps of video that they just aren't used to the higher, more realistic framerate.
So, I would highly recommend seeing the movie in a standard theater.