Only sync songs that Spotify dont have?

[Boedker]

Hey 

I just got premium service yesterday and overall its fantastic!

However i have i little request:

Let's say i have a playlist with 100 songs(could be a lot more). 10 songs are not in the Spotify library. Is there any way I can sync. ONLY the 10 songs to my iPhone that Spotify don't have? I know I can use the offline mode, but that will sync. all 100 songs, even the songs that can be streamed from Spotify :S