I did not started to work on >SD7, SD9 etc... series
Their new style format is a midifile format, a bit like Yamaha
I am actually working on the Audya style format. vArranger can play Audya styles with any midi synth, but the audiodrums and the live guitar will probably be played only by the internal Software synthesizer, as they are kind of audio tracks
You are right where it comes to sd7/sd40..
But the sd9/80/90 also supports audio guitars and more... its not just midi with audio drums..