A tough book to review without spoilers, but I'll try.
It's an adventures-with/against-dinosaurs tale, no doubt about it. The kids get chased by a variety of incredibly large dinosaurs -- larger even than you might think (apparently, thanks to GMOs and other side-effects of the 21st Century, the dinos that were brought back from extinction are actually BIGGER than their original kin. Yes, the book has interesting little details like that) and we have a few saved-from-the-jaws-of-death (literally) moments. Mostly it's just exciting enough without being too scary (I'm pretty squeamish and easily alarmed) though there were a few other incidents that were surprisingly violent. The book is much more than just a B action movie, though.
Like "Jurassic Park" (the comparison is inevitable and, fortunately, the author addresses the elephant in the room fairly early in the book) the book features an exploration of man vs. nature and the dangers of overextending science and playing God. It has a deeper layer regarding government and political power, as well. When is the person in power a leader making unilateral choices for the good of the people, and when is he a corrupt dictator who can no longer listen to any other opinions? I was pleasantly surprised by the multi-layers and depth that a middle grade story about dinosaurs achieved.
As for the writing style, I found it engaging and entertaining. The story moved at a good pace and I found myself eager to continue reading chapter after chapter. While I'm not sure our protagonist will ever be a "kindred spirit" and I found it rather hard to warm up to her, I did appreciate her by the end of the story and I really liked her best friend. The world building was mostly solid and yet a few points really did not make much sense and I hope will be addressed in the sequel. The plot twists were mostly surprising yet suitable for the story, and yet...
The book has a major lack of conclusion much to my annoyance. While perhaps one major plot thread may have maybe-possibly have been wrapped up it was not satisfying and two other major plot threads were not resolved at all. I realize that publishers like every book to have a sequel (or more) and perhaps the author had intended this as one continuous story. But, the ending was just so completely without resolution that it was quite irritating. That said, I did enjoy the book on the whole and will continue with the sequel since it is available at my library.