So I gotta say I am pre-biased in favor of this movie.... Beyond the whole Drew Barrymore affinity that I freely admit to, I have been to Austin TX a number of times (love the town and the culture) and have even attended a Roller Derby event in Austin.
I loved this movie. Very entertaining, lots of LOL moments and was even engaged for the action scenes. There even was a surreal moment as they show the characters watching a movie in the Alamo Drafthouse in downtown Austin (the same place I was watching the movie). The story, the development of the main character from a meek girl to an empowered young woman is good and believable, the characters are likeable and relatable, and you leave the movie with a good feeling.
Really, if you have a chance? Check it out.