I pretty much use the PSR as an arranger only. I have used midi files on a limited basis as a back up to assist with me my voice lessons.

I have created a song sytle library that I store in folders A to C, D to F etc. I have hundreds of songs stlyles stored. This library supplements use of registrations. What I find convenient is that I can assemble gig disks on the fly using this master library which I keep stored on a 2 gig flash drive.