That's probably a Good Thing, for composers in general. In this case, after a single listen-through, he's right to feel a little nervous. Unfounded, really, as the opus stands up on its merits; most of the criticism stemming from the genre and personal taste, rather than its existence. I'm a drummer, so found it a bit difficult (no, rather too 'edgy'...), as it's properly composed (for the genre...), but executed too mechanically, with 'artificial' variances. It's true, though, that some drummers do play like that, so... Not keen on the incessant insistance of the beat in general, but it fits the subject. I'm not a great fan of 'riffs', so maybe not the best judge of music in this vein; the bloke has done well, and I did manage to listen all the way through (not always the case with me..!). It won't go into my collection, but, then again, I didn't buy the Gojira disks, either. Good luck to the fellow. He gets a 'Thumb's up'.