I'll be honest and say that I haven't beaten many Castlevania games.  If anything, they're not until at the very least in the Saturn/Playstation generation.  Just because I've only beaten a handful of these games, it does not mean that I don't recognize Vampire Killer from Castlevania.  If I remember correctly, it's the first stage music in Castlevania.  As iconic as the original theme is, I can't help but jam to the Saturn Rock Version of the song.  I just myself nodding to it as if in acknowledgement that this version is dope.  If there's one thing about the Saturn version of the game, it's that the Playstation doesn't have the Goth or Rock version of Vampire Killer.  (This is to my knowledge.)  Eventually, I'll try to find some time and grind out some Castlevania games to finish.  Until then, I'll just keep listening to this theme.