Story: I think the story progressed nicely as you watch the rise and fall, the hardship and the many lessons our main star endures to reach his goals. Many sports animes tend to focus on the main character working from being a total clutz with zero talent into the world's greatest *insert sports here* player. This anime moves slighly away from that and we start to understand that, life doesn't end when you become great, there are many more lessons in life one can learn, lessons from many different areas. This series mixes fantasy well with reality, making it both informative (learning about the rules and regulations of tennis) but at the same time entertaining with the various skills and attacks observed throughout the series. Another great feature of this series is the use of fillers to the right amount. Unlike other series that tend to have fillers to no end and bores the audience, Prince of Tennis actually uses just enough fillers in between matches for comic relief, contrasting it nicely against the seriousness of the matches.
Art: Not really much to say about art. It's pretty hard to keep coming up with new things, so you find certain frames etc. being repeated. However, they are used in repetition well, so you can't usually tell if you doesn't watch it too carefully.
Sound: Same as for art. But I found certain areas, the sound didn't match too well with the situation being presented, it was either too serious or not serious enough. Hence the given rating.
Character: I would have to give credit to the characters in this series. It would been really difficult trying to come up with so many different characters and be able to make it so that the audience can distinguish between each based on looks, personality, playing styles etc. It was great watching better, stronger, more skilled players being introduced all the time, and it keeps you entertained with the different playing styles. Also, although the characters do not seem to age greatly as the story progresses, however they do develop and become more mature, learning the lessons and achieving their goals. It's nice watching them grow up as the story progresses.
Enjoyment: The series is very good. Other than sound, which pulled it down a little, overall you can learn a lot from watching this series. I enjoyed every episode and I find that none of the episodes are a waste of time. They come together nicely to make the story whole.
Overall: The series is great and highly recommended.
