Vquestor,
I looked at the comparison charts, you are are right, it doesn't support soundfonts, I thought it did, my mistake, sorry!
Well you can always install an Audigy (2) and convert your songs to MP3/Wave and put them on a laptop or CD .
Okay that is kinda useless if you already own an arranger, you can just plug the keyboard in your line-in and record those midis.
But still...
You are missing something if you don't have a soundcard that supports soundfonts .
If you look around you can find some real good soundfonts, and of course you can make your own.

Greetz ,
Marcel