A useful thing in Sync Manager - Improvement Request

One thing that is totally stressing is the fact that when you go and sync your library with your USB pens you don't know automatically if you have space or not on the USB. It's something so simple to add... Many times it's a trial and error until I now I have space. 

This is something easy to implement, as you select the playlists you want to add it should automatically calculate size, show it and compare it with the USB size to say how much you still got left!