Snake - everyone is going to have a different opinion on how extreme it is. People who are not coaster fanatics will probably consider it to be more extreme than those who love coasters. I suggest you ride it for yourself and make your own opinion.
I love inversions so Collossus impressed me quite a bit. I could see the ride not being for everyone though. The 4 spins near the end of the ride got me pretty dizzy.
The back half of the train provided a bouncy ride. I haven't ridden it since 2002, but from some of recent reports I have read, the coaster has gotten quite rough.