Maybe I should restate that to other metal vocalists in general.
Alexi's vocals are so wild.Especially on Hatebreeder album, they're very harsh.Not so brutal, but not like scream.Alexi makes this balance.Also on Follow The Reaper, I love his scream when he shouts like "YAOOOOOW!" like in Mask Of Sanity's entrance or Taste Of My Scythe.He is mind-blowing.
On Are You Dead Yet? vocals are nothing more than a failure...I want their vocals to be like on Hatebreeder or FTR again.
I like HCDR and AYDY vocals most, they sound most natural, on the other ones it sounds like he's trying too much to force his voice to sound like something else. Blooddrunk vocals are just weird mostly, not his voice but the way he sings/screams/growls whatever.
But it's good that the vocals have changed in every album, so every album sounds a bit different on the vocals