I had the TV option on our BMW touring, and used it twice I think it was. Then had it on our ML and never used it.
So didn't bother on our A4 avant, and again didn't bother on the A3, I am going to add a din sized dvd player in the glove box where the 6 cd changer goes, and a headrest screen. That was my daughter can watch a film with headphones whilst I listen to my tunes from the MP3 player or listen to the radio as normal.