The custom voiced version of the Legend for Krank is phenomenal / crisp, clear and just crushing.
I have used or am using the following speakers>
Governor - V30 copy, a bit more focused on the upper mids and more aggression
Black Powder - crisp and fairly trebly, works great with baritone and for death metal
Cannabis Rex - almost opposite of the Black Powder, huge tone, very round and full, soft treble response.
Also great would be the Texas Heat for metal.