Good Day John - many users (maybe just me?) sometimes use a mix of Realtracks/Realdrums and MIDI to effect the music creation process. BIAB is music creation software and it should not be necessary for licensed users to scrounge around to obtain a fair quality integrated GM sound. PG still markets and sells MIDI styles and should support the styles with a decent GM sound set. That is merely my opinion as a licensed user - as an example I have not indicated in the post that the acoustic guitar should sound like a 1937 D45 Martin or the acoustic piano like a Steinway or whatever. Those users would then target the Garritan's etc. Just a solid integrated GM sound set would do fine.
Regards
Roy