I've been doing a lot of research lately on camcorders and both are nice for different reasons but if you want the best camera of the two for short films, go with the Canon R100 because it has a microphone input and head phone output. You can make sure your sound is as great as your picture which makes a big difference.
The R100 is the camera I'm trying to get for my Christmas present. I wish it had 24P but for this price it's more than I could ask for as is.