This is a danish band. Their style of music is called noisecore; it's about making noise
Link
Noisecore...I have heard of that genre for the very first time. It looks like people are stereotyping about Metal and created this genre...LOL
I listened to it, and the screeches just pierced through my ear drums. I wouldn't call it extreme, just disturbing. Even a high-pitched whistle can be this annoying...LOL