I have not read Divergent, I saw the movie, so I cannot compare the two. Insurgent is exciting and fast paced. It takes a few pages before the story really starts, but from then on, you are in a roller coaster.
A lot of people will probably compare this book with the Hunger Games. And it is definitely in the same corner. Both are about a young inflammable girl that is part of a rebellion against oppressors. But it is a completely different story. Although Tris can be as caught up in her emotions as Katniss could. I think Veronica Roth goes on a bit too long about her emotions. But then, I am not a young girl.
If that does not bother you, this is a great book!