From what I have been hearing, it is incredibly well done and I think you will be missing something important...but that's entirely up to you, of course.
All the credible reviews have praised this movie .. even Roger Ebert .. and said it is so well done, true to the real story, and a portion of the proceeds will go to building the Flight 93 memorial in Shanksville.
No greater love hath a man than to lay down his life for his friends."
Never Forget!!