Hold on, why is the PC88 version slower? Is it like that on the real thing too or just an emulation issue? Either way, i prefer how X1 sounds overall (the instrument mixing in Cursed Oasis - Sand Castle for example is a clear winner for me), but PC88 has it's own charm too.
English commenter here. I've only played the MS-DOS version of "Sorcerian", so I honestly feel that the PC-88 version's tempo is too slow. The X1 is a bit better in that regard, but still not quite there. The DOS version actually supports MT-32 units, as well as most SoundBlaster cards (these can use OPL, OPL2, or OPL3). Of these, I've only heard the OPL1 rendition, and it has much more limited instrumentation than the PC-88 or X1 versions.