that is purely a question of oppinion
Generation X - band - ended in 1981.
Generation X - band - was created in 1976.
The GCF is 6.
The GCF is 4.
The GCF is 16.
They are a Power Metal and Symphonic Metal band.
Heavy Metal/Rock Metal
Neither. They are a psychobilly band (psychobilly is a sub-genre of punk music). Also, "metal" and "heavy metal" are the same thing.
Metal Church is a band that started in 1980 by 5 people that creates heavy metal music. This means that Metal Church is primarily heavy metal music band.
Quartz - metal band - ended in 1983.
Pantera is a metal band. Anthrax is both.
Attila - metal band - was created in 2005.