The thing that drives me far and quickly away from the "Pinky and the Brain" (sorry, just can't resist -- love that tagline
) books is their particular writing style.
IMO, If you're going to write in the Dune universe (especially the "Dune 7 finale")... then at least TRY to mimic the style of Frank Herbert to some extent, which was somewhat similar to what Isaac Asimov did in the Foundation series -- very rarely does full-on action take center stage, it's usually after the fact, or more contemplative or interlaced with the character's thoughts at the time.
Instead, with the newer books by Pinky and the Brain, you get to read firsthand about meks pulping brains as they go by, arms and legs being ripped off and flying about, etc. In a word, YUCK. It's a jarring transition, in short. About the only thing they copied from Herbert Sr. are the quotes at the beginning of each chapter -- and even those fall short. The chapter quotes from the "original" Dune books really made you think and pulled you into the universe, making it a richer environment. Not so much with the newer books.
And the less we say about their so-called "intricate plots and twists" (which practically shout themselves off the page)... the better.