7 of 10. As much as the tedious and overused music Rocky music gets used, having a serious critique of it and the use of music in training was definitely an unexpected bonus. While it creates a story about the underside of boxing and gambling, it does so by making it sexy, amusing, and dangerous.
After Foxcatcher (2014), I was hoping more films like this would turn up. Going beyond the simplistic and deceptive underdog sports/fighter hero stories is very much needed even if it lacks the guaranteed easy box office cash. It lacks the "based on a true story" element, but definitely feels as if you're observing a composite sketch of something people have actually seen.
The result is something along the lines of The Fighter (2010), with smart casting making up for lesser acting talent and an understanding for their setting and its visual/audio qualities making up for less production money.