I believe adding sound banks via sysex will overwrite a previous bank. Say for example I export bank 16 as a sysex file and then send that to someone else, when they load it into their machine it will load into the location that it came from overwriting bank 16 on their machine. You can however save individual patches. So if I export just one sound from bank 16 and my friend loads it into his machine, it is only saved into memory and will be lost as soon as he twiddles a few knobs or powers down the unit. This single sound can be saved to any location you choose by following normal saving procedures.
I think that’s correct anyway.
It might be possible to extract individual patches in some librarians. That way you could audition the individual sounds and save them in a location of your choice.