Regarding Ben Jackson's inquiry for MIDI files of 88-note Welte and QRS
rolls: As part of the piano roll scanning preservation project, I have
scanned and created MIDI files from almost 1000 piano rolls so far.
Many of these are 88-note QRS rolls.

The MIDI files from 1922 and earlier rolls/songs are available for
download from the piano roll scanning section my web site.  The URL for
this section is  http://www.trachtman.org/rollscans/ 

Regards,
Warren Trachtman