I don't usually rate films badly but this dissapointed me quite a lot. The film strays so much from the book. I'd say if you haven't read the books it's a good stand alone film.
I thought that the movie was very rushed and I didn't get the connection between all of the characters. For example I felt more of a friendship with Minho and Thomas compared to Thomas and Chuck. They also played the plot out completely differently to the book and skipped out things like the telepathy with Teresa and Thomas.
The cinematography was alright except it was set in the dark and was quite hard to see everything going on but the cgi was very good.
I definitely recommend reading the books if you watched the film first so you get more of an understanding of what's going on.