I enjoyed learning more about Phil Stutz the person I want to start by saying I bought the book The Tools before seeing the movie. The book is incredibly written and goes into detail about many subjects lightly touched upon in the film. I would recommend getting the book if you are ready to make changes in your life.
I enjoyed seeing the interaction between Dr Stutz and Jonah Hill. It kind of feels like there might not have been a clear plan for the format or direction of the movie. The movie starts out on a more serious note and then halfway through it gets more playful with Jonah revealing they are on a soundstage and he is wearing a wig, etc. It kind of pulled me out of the immersion of things. The second half of the movie was almost a completely different movie.
I agree with another reviewer on here saying it was odd the movie would take two years to make. I think that caused some issues with the final product in terms of continuity. Having Jonah's mother in the movie also seemed disjointed and did not add much.
My favorite parts were learning more about Phil Stutz the person in addition to The Tools. When Jonah talked about his weight problem, I felt it was a bit of a safe topic. Dr Stutz talks about his own brothers death but Jonah is still avoiding going too deep on camera about his brothers death. I think as painful as it might be, that would have been a deep connection with the audience.
Again, I highly recommend getting the book to learn more about the Tools!