I have made some modifications to the original plugin, so that you can specify a list of Words (feat., with, & etc.) which should be used as split.
I also made a check so it only splits if there is more than one ArtistID assigned to the track/album to avoid it splitting Prezioso feat. Marvin - MusicBrainz.
It should be possibly to modify my modification to always replace the spilt Words with an & in the brackets.
I will post my version of the plugin when I come home.