Update: found the "secret sauce" path after installing Roland Sound Canvas VA and now I've got official SC-55 emulation in my midi player. If no one knows what I'm talking about, well then- EQUIP THE RING! Heh.
Just in case, note that you need to change the Map Mode to SC-55 in Option, System. It seems like the best way of running it is in SAVIHost and with loopMIDI, but you probably already know it (if not, check Phil's Computer Lab video on YouTube). Then, in order not to have to change the map each time you launch it, you can use the PlugIn, Save Bank As... function to create a configuration file, but do it only with a freshly launched instance with just a map change, in order to prevent any other modifications being carried over from a game or a track.
Remember also always to check the set-up programs of DOS games, as they often had special settings for different types of MIDI devices. Sound Canvas, SC-55, or SCC-1 is preferable, but some games only supported General MIDI (GM). Note that there were also older Roland devices like MT-32, so if the label is something vague like ‘Roland device’, it can be misleading.
Finally, some games have tracks that create problems for each other, because when instruments are modified or even a part has a certain instrument set, these may not be reset between tracks, which results in wrong instruments being used in subsequent tracks. This is especially noticeable in Duke Nukem 3D with certain tracks. The solution is either to launch the game again once you reach a level with a weird-sounding track or to reset the SC VA while it's running and reload the map.
As for the SC-88 and SC-88 Pro maps, it seems that scant few games in the West used those synthesizers, as they were rather expensive and didn't have expansion-cards or daughter boards based on them, while games would soon switch over to CD music. The full version of ‘Grabbag’ included on the Duke Nukem: Atomic Edition's disc was composed using SC-88, as was all of Shadow Warrior's music, but apart from a few shareware-only tracks in the latter, they were all mastered as CD tracks.
Those synthesizers did see some use for MIDI in Japan, though, one example being Touhou fuumaroku, some extra arrangements of tracks from the other PC-98 instalments, and Touhou Koumakyou, but ZUN didn't like them and replaced them with Roland Edirol SD-90 for mastered CD tracks even as he was working on that last title, and he's been using it ever since.
