Fantastic! One of the most engaging books I've read, and not only of the category of sci-fi. It has scientists, police, conspiracies, extraterrestrial life, and even an old research facility with lots of secrets.
I've actually been putting this review off for several days now, and I still don't feel ready to give it, so this is just gonna be short, and I'll revisit this again when I've read the book a second time.
If you are into hard sci-fi, and are fascinated by first contact stories, this is a must read.