The only time I've been able to compare a movie and a musical is The Producers.

I saw the play first and was amazed at how good it was. It was over-the-top and politically incorrect in all the right ways.

Both of the films were great, but I just didn't like them as much. I dunno if it's because I already enjoyed the play so much, but especially during the more elaborate parts ((SPOILER)"Springtime for Hitler" and "Keep It Gay" in particular) I found myself more entertained when they were performed on stage.