The Irregular at Magic High School is a bit tough to follow and understand for the average viewer. It's a very scientific anime, which I love, and even a sciency person such as myself had to watch it a couple of times to get a full understanding of the science and magic behind the series. This ONA is a great watch to get a head start on the show before watching it. I'd say it's almost essential to watch. The best part is it's short and sweet and to the point and the chibi characters are pretty cute and gives the main characters a quickintroduction.