I think gzarruk mentioned this, and I've said it before too, but it's not JUST about whether we "like" Jeff's voice or not. It's also how it fits in the music. Like him or not, but David Lee Roth's voice range and timbre FIT with Van Halen. As great a singer as I think Bono is, he would sound like shit in Sons of Apollo or Dream Theater as well. You listen to the early Zeppelin, and each member has it's "sonic range" of sorts, and no one is really competing with each other. I think more than any of Mike's bands, SoA seems to have five musicians all competing in the same sonic space, and FOR ME (I don't expect anyone else to share this) the melodies and parts aren't compelling enough to consistently cut through.
To copy Bosk:
-Neal Morse Band: automatic buy
-Transatlantic: automatic buy
-Sons of Apollo: wait and see, but studio albums are a likely buy (didn't buy Plovdiv)
-Flying Colors: automatic buy
-everything else: not likely purchases unless I hear something that truly wows me
I don't think of it this way, but essentially I'm buying Neal Morse records with Mike on them, not the other way around.