Really enjoyed the first 2 thirds of the book like many other reviewers. However the moment Ridley got on the sub it went massively down hill. I finished the book but found it a struggle to get through.
So Kasinsky, who wants to attack the west was then happy just to basically ruin the world? That didn't make much sense.
Also once they were changed into ridgebacks they had one clear weak point allowing them to be killed by spears. They seemed to be more than capable of operating drones etc but we are supposed to believe they wouldn't attempt to protect themselves?
I wish it had remained a spy novel