Probably you noticed that my avatar is a photo of Steve Harris, bassist of Iron Maiden. I have quite a few years that I started to listen this kind of music, even when I was in the JWland. Although it was a "no-no" in the borders of JWland, I knew a lot of brothers and sisters that listened and loved this kind of music. I remember some articles from the Org. about the dangers of this kind of music. Also, when you wanted to apply for being a Bethelite, one of the questions is "do you listen heavy metal/rap". One CO told me that the Org. named one band in its publications: Guns n' Roses.This attitude of hate and prohibition was not exclusively from the JW, but also from other religions in general.
When I was in the university, one professor influenced us not just to listen heavy metal, but to analyze its implications in the culture, society and religion. He recommended us to read "Running with the Devil: Power, Gender and Madness in Heavy Metal Music", from Robert Walser, and to see the documentary from Sam Dunn "Metal: a Headbanger's Journey". We learned a lot from those works about the roots, history, influence, behavior and other stuff related with heavy metal. I recommend you too to review these works if you like heavy metal.