I think that ALL of the people who claim that V is the untopped and untoppable Symphony X albums, should give up listening to them, because they just complain and moan (see the official forum, for example).
To me, the untopped album is Paradise Lost and its perfect balance between melody and heaviness. I like V a lot as well, but to me PL has better songs.
With this said, Iconoclast is not actually "very comfortable material", but rather "very heavy material": lots of guitar riffs (too much!!), poor orchestral sections, no piano/guitar interplay (I'm thinking of songs like a Fool's Paradise for example), very few vocal melodies (the only epic chorir worth a mention is the one on the title track), most of the songs have no vocal harmones at all, and too much grunting (Heretic, Dehumanized, Prometheus, etc.), and in general lack that fantastic hooks that made the previous albums instantly accessible.
And, last but not least, tell the reviewer that iconoclast is NOT a concept album, but rather a "theme" album