Neal, judging from that pic, I'd lay off the late nights and the bottle for a bit. Just sayin'...
On topic, yeah, I really like his voice for a lot of the reasons that have been mentioned in this thread. But it's funny. Before Tertimony 2, I never in a million years could have possibly predicted you would EVER hear a death growl from Neal. As diverse as he can be, that is one style I just never would have guessed you'd hear on a Neal Morse album (although I suppose if I would have taken a bet as to whether you'd ever hear a death growl on one of his albums, I guess technically I would have won, since there are actually two of them on T2). But I honestly can't tell if it's him or Mike (or both). Judging from when he and Mike do it during Stranger In Your Soul on the Whirlwind Live DVD, it could be either one of them. I haven't watched the whole T2 doc yet. Maybe they show it in there?