I think this release was generally good. All songs were pretty enjoyable, with the best being Chaboo Chaboo imo.
I don't have any problems with the vocals, and am generally neutral about them unless they're terrible or the lyrics are aweful (especially if they're in English). On the other hand, I've only started listening to 12012 since their self-titled album, so I don't really know how much they've changed since their earlier releases.
Finally, if I had to give a score, Deicida of Silence is easily a 3.5 or 4-star release.