I have always used and preferred MIDI over audio. When set up right, MIDI sounds amazing. Then there is the file size and easy manipulation of the data. Basically, MIDI is my preferred way to work.
As soon as I have a bit of time, I will publish some of my MIDI files which cover all the classics starting from the swing area all the way to current rock and pop music.
If you happen to use a Yamaha Genos, then you are in for a treat. Lately, I record straight from the Genos to USB which means, that those files will play correctly without editing on any Genos.