they were noise rock at first, on Cop, Young God, etc, which is probably their weakest material, albeit most extreme.
THey got interested with Children of God, and peaked on Love of Life, Great Annihilator, and The Burning World(yes, the band peaked a lot). This material is much more accessible and less extreme, but is simply good music.
Also try the side project World of Skin.
In answer to the thread title: The Great Annihilator