Great for the price I paid, which is free since I signed up for the Kindle Unlimited free trial (and set a calendar reminder to cancel it). Hey, there are a lot of books that I won't even read for free so this is still a compliment.
Good pacing and very nice mix of real quantum theory with some made up stuff, and an accompanying final "chapter" that tells you exactly what was real and not. There were some hints at time things in the story which the third book Quantum Time will surely get deeper into.