Holy shit, guys. I've just tried the YMF-718S on my P-166 system with the drivers posted above. Looks like it has soft-synth. My only general midi devices until now were AWE32/SB32/AWE64.
I've only tried it on Doom e1m1 and Duke Nukem 3D title screen, but I defininetly like the way the samples sound on e1m1 as compared to the AWE. Also, it has no issues with Duke Nukem (AWE series sometimes produced garbled sound in this game).
It's not in the same league as the YouTube recordings from SC-55 and MU-80, but it's SO much better than AWE. I've been thinking about getting one of those MIDI modules, but I don't think I can justify spending 100-150 bucks on them now.
The only drawback I've noticed so far is that the music can stutter a bit, since soft synth relies on the CPU. But the only instance I've noticed it is in Duke Nukem 3D main menu screen upon loading a new map.
And all this time I've had it just laying around, thinking it's a cheap SB clone. Just wow...