I discovered Stortregn when Impermanence came out, and I really loved that one. Xeno Chaos is a great track, and I have no doubt that the new album will indeed slay.
I've always enjoyed Kataklysm, but I thought the last album, Unconquered was terrible. New track sounds pretty good, so hopefully the new one is a step up. The Houde albums, Sorcery and Temple of Knowledge, are classics, and a few of my favorites from the Maurizio era are:
The Prophecy
Shadows & Dust
Serenity In Fire
In The Arms of Devastation
Waiting for the End to Come