Ultimate Ninja Storm 3 can be a fun game if you're a fan of the show or manga, but it doesn't offer much to those who aren't. The combat is simplistic but works and allows new players to the series to jump straight into the game.The story, whilst changing how some events play out, still tells the journey of Naruto and the Ninja War.
The game hasn't really been tuned up the way you'd expect from a sequel and feels a lot like Ninja Storm 2. Whilst this isn't a bad thing as it still has plenty of new playable characters and continues the story, you instantly feel that you've played this game before. The online battles are still a mess, with people being encouraged to repeatedly use the same attack to win and no real incentive to try any of the lesser characters, it gets dull quickly. On top of that you have connection issues with most matches you join having some sort of delay. This can be side stepped if you host a match but then the other player will be in your shoes. So don't expect this game to have a strong playerbase for long.
All in all I'd say this is a rental or buy when it's around £20. There is no need to play this game immediately and it doesn't bring enough new features to the table to warrant a full price purchase.