I have just started watching the second season, and realized that the orignal music is indeed missing.
The episode title "Operation: Spoilsport" which played the song Eve Of Destruction ( well it was supposed to anyway ) but it didn't. I had no sooner told my son that they would be playing this song, but instead it was some unknown piece of trash. My next thought was that I must have been mistaken about this episode, but then Ralph told Bill that his radio just played Eve of Destruction.
If I had realized that the music had been altered, I am not sure I would have bought the series. I have not bought a few shows were the music has been altered, such as "Tour of Duty".
They should have to put a label on the DVD's when they have altered the music, imagine buying a musical like the Wizard of Ozz, or Saturday Night Fever etc., and finding out they have changed the music.
So this set gets a 3 instead of the 5 it deserved. Oh, and the next time I see one of those commercials telling us how bad it is to download Movies and Music, my opinion will be too bad. If your going to rip us off with removing music and double sided DVD's, don't going looking for sympathy.