Hmmm, one of my favourite growls is in the song Firestorm by Xandria, because (female) vocalist, Lisa Middelhauve normally sings in a really soft voice but after this instrumental section of the song she suddenly growls a line amazingly well, the level of distortion and pauses between words are absolutely spot on and the blast beats played with each word accentuate the growls really well.
That is what comes to mind first for me whenever someone asks about the best growls anyway.
Whether or not it's better than Mike's I don't know but it's the growl that I find most memorable anyway. Possibly because it stands out so much against the rest of the song, whereas most of the time if growls are in a song they are in it a lot rather than a single line.