Music in pins for me is about moments. I will never buy or reject a pin on the basis of which band is its theme. The gameplay always comes first. But, when the music fits the moment just right, it can suddenly be ALL about the music.
Case in point..I knew average about Metallica when the pin came out. I had experienced what the mainstream had brought me, ES, SBT, those sorts of songs. I was into the game rather than the theme. But, after one the later code updates I noticed that ECMB would alternate the backing music and the one with all the guitar solo was far better (see, I STILL don't know which of the two it is, haha, maybe RTL?). The more I played, the more I hankered for that to be the one that played. Then I found out you could set it. Now, THE moment in Metallica for me is when I can get the machine just blowing up with that music playing, and lights everywhere, and jackpots everywhere and THAT music playing.
What happens in the rest of the game comes and goes but that particular segment is totally defined by the music.