Varese's initial release of Gremlins II is really perfect as is and I wasn't interested in the Club release. Same goes for Santa Claus: The Movie. I did buy Quartet's 3-CD set but I listen to the album program more than the full score.
I couldn't do without the Gremlins 2 expansion. In addition to what I think is essential added music, I also believe the sound quality is much better than that on the original album.
The expansion got criticized by some for being one of Varese's albums mastered too hot, but that is not true at all. Unfortunately, that critique only sends mixed messages to the label when we want sound done "right."