I have directed both. Basically, the 2012 version is based on the Broadway revival. The harmonies and orchestrations are updated to a more contemporary sound and the song "Beautiful City", which was written for the film, is added. Also, the opening sequence, "Tower of Babble" has more contemporary quotes. Personally, I think the music in the 2012 is harder for students to learn. Both soundtracks are on youtube. You should listen to both before deciding which you want to produce. Hope this is helpful.