I give the book 7.5/10 for how I enjoyed it. To me, the book read as if the first person character in "Catcher In The Rye" were writing his experience in the Corps. The author does have a refreshing writing style and an interesting turn of words.
If you like the genre, if you want to know about the culture of Marines and sniper training including the Barrett rifle and Desert Storm, you will probably like the movie (if it is faithful to the book). I usually like any movie about soldiering and war.