3.5/5
Compelling concept, I liked the scientific approach to the topic. The last 30% got really interesting (with multiple Jasons in one world) but it felt rushed.
In an attempt to show the urgency of some situations, the book completely failed to convey the sense of time passing. Almost a month passed in the story, Jason said it felt like years for him; but it felt like days for the reader (or to me, at least).
I found the writing style very annoying; the short paragraphs, the List-like paragraphs made me almost give up. Up to a point, I thought it could make sense - it could be justifiable - because of the 1st person pov; we don't always think in coherent sentences/paragraphs after all. But then the 3rd-person pov chapters had the same style. And the frequency of the list-like paragraphs, almost like bullet-points, seemed to increase as the story went on.
There was barely any characterization for anyone other than the main Jason - Daniela and Charlie felt like shells of what they were supposed to be, like stand-ins.
I would've loved more 3rd person pov chapters, maybe on the other Jasons, to see them interact with each other, etc.
I don't know how else to describe it, but this felt like a book written specifically to turn into a movie.
It lacked heart, it lacked life despite the multiple attempts made to make characters matter. The settings, characters, etc were not descriptive enough; everything was described vaguely enough, everything was generic enough so it could be made into a movie easily. It almost felt like just the plot-line written down; as if an adaption is supposed to fill in the gaps, to bring the story and the characters to life.