How to import a playlist and songs without getting duplicate entries in the media library?

I have a folder full of music and an m3u playlist of a random subsection of said music. I scan the music folder for media, works great. I then import the playlist, but this adds duplicate entries in the library (I was hoping SB would be intelligent enough to not add any tracks already present).

I did try using the 'Exorcist' addon, and while that seemed to work on the library, it also removed the entries in the playlist rendering it useless for my needs.

You encounter the same situation if you do it the other way too (i.e. playlist first then scan folder for media).

So, short of whacking the playlist and the list of songs in the folder into a database and writing a query to output the list of songs not present in the playlist (which is a little excessive), is there anyway using songbird to do what I want to achieve?

Al