Very nice topic.
I use to listen any kind of music and I love many singers or group. First of all I love Metal and Judas Pries, but I also like Jazz, Blues, Folk, some italian singers such as Vinicio Capossela,, but if I have to think to a 'Guilty Pleasure', well I love Bee Gees.
In my opinio they produce one of the best metal songs of ever: TRAGEDY. Now try to imagine it played by Priest
If any metal group will read this, try to play it. It's fantastic.