Isn't SB Pro's dual OPL2 support only relevant for like... the demo tune played by diagnose.exe and that's about it? Most of the software that actually used 2xOPL2 (all three games or whatever) seemed to prefer Media Vision's addressing. So if dual OPL2 is important to you, that's probably the better target. Dunno if the FMonster does both. It has been a while since I last compared all the I/O addresses of various card configurations, but I think I came to the conclusion once that a card with both SB Pro 1.0 and PAS dual OPL2 compatibility would break mono 1xOPL2, or OPL3, or something like that, and to do it right would probably require a software switchable I/O address decoder and/or mixer.