Harmy said:

So just from a quick comparison, the Belbucus isolated score has the normal soundtrack where there's no music playing in the film, whereas the editdroid version has just silence there.

This is the main difference between the two. Also, Belbucus did something to the Cantina music to make it sound more like a live performance. Full details here.

As is there a PCM version of any isolated score, for a possible use on the BD version?

I think I still have the Belbucus ISOSCORE file as a WAV file somewhere.