This movie was pretty damn entertaining and creepy. Sure it's not believable in so many ways, but just turn off your brain and enjoy a great shark movie. This could easily serve as this generation's Jaws. There were the same number of creepy shark coming visuals to make you jump and the movie was the perfect length for this kind of source material.
I would definitely recommend that anyone who was interested in seeing this do so. It was a fun, scary movie that will probably have a negative effect on me swimming in the ocean for a while.