Maybe to answer the original question:
MMC3 - UxROM 16k PRG banking can be simulated with 2 x 8k PRG banking. 512k PRG + CHR-RAM was a used configuration (e.g. Mega Man 4/6)
MMC1 - MMC1 has 16k PRG banking, main disadvantage is the serial register interface, 512k PRG + CHR-RAM was used (e.g. Dragon Warrior III/IV)
VRC7 - Like MMC3 but Famicom only and relatively rare, 512k PRG + CHR-RAM was used (Lagrange Point)
As far as FCEUX goes, the oldest version I can find (2.0.0 circa 2008) runs Owlia and also definitely supports 512k BNROM. I think if 2.2.2 had some problem with Owlia it was not about the PRG size, probably some other transient bug.
GradualGames wrote:
It occurred to me that now Mapper 30 has been assigned the above configuration, and presumably this website and its wiki are considered the authority for emulator authors to use for mapper documentation, perhaps all I need to do is change the mapper number to 30 to be likely to be supported by more emulators going forward.
I would say that an emulator is far more likely to have a 512k-accepting mapper 2 than any mapper 30. You should really only use mapper 30 if you need the flash save capability or CHR-RAM banking. (I would doubt there's any emulator out there that supports mapper 30 but not 512k mapper 2?)
Memblers' Cheapocabra/GTROM (111) has pretty similar capabilities too.