How many copies of Street Fighter IV do you own? Two, three different copies? How do you fancy buying another.
Looks like you'll get your chance soon. The BBFC's revealed a rating for Super Street Fighter IV Arcade Edition that's supposedly due out in June. Presumably the new version will include the four new characters from the arcade version of the game: Yun, Yang, Oni and Evil Ryu.
Of course, this classification could feasibly pertain to DLC, but knowing Capcom we wouldn't be surprised if this turned out to be a retail release.