The answer would take several pages and most people wouldn't understand a half of it anyway, but shortly: I just am.
Out of those three, Behemoth. I liked Sepultura until Chaos AD, Slayer's Reign in Blood and Seasons in the Abyss are classics, but Behemoth are still blasting even today. Still, I'd choose Keep of Kalessin over any of them if their last EP was better, looks like they are losing it (as well as losing the singer). If you really want "evil" (for some reason... though I personally think the only "evil" is human stupidity) the new Rotting Christ album "Kata Ton Daimona Eaytoy" is pretty good, they still have the "edge".