The Advanced Options allow you to control how SongKong decides which songs to delete and which to keep once it has identified duplicates in your collection.
Why does this matter? You may have a preferred audio format. You may prefer lossless files or files that are for all intents and purposes the same as the original CD track because when they were ripped to the hard drive no data was lost. Alternatively, you may opt to keep lossy files or compressed versions of the tracks because they don't take up so much space on your hard drive, iPod, DropBox etc. The Advanced Options allow you to decide which audio format you would like SongKong to keep when duplicates are found.
By default the Advanced Options uses Audio Format to decide which files to delete and which to keep and 'lossless' files are set as the files to keep. You can, however, change the preferred audio format to suit your needs.
As well as Audio format SongKong allows you to delete duplicates by a range of criteria including Bitrate, Track Length, File name and File Creation Date.
You can order the priority of this criteria so that the files SongKong keeps once duplicates have been found are the versions you really want.