I was really hoping for some real closure with this movie. The boys would make it to Koshien and we'd see them kick everyone's butts in the tournament. Alas, we don't get to see that. We see the boys make it to Koshien but then the movie skips to their graduation. We never really find out how they performed.
That doesn't mean it was a bad movie. The two new characters, Akahoshi Shoji and Hamanaka Taiyo, are great additions to the cast. Without them, I think the movie would have felt repetitive since the team pretty much does the same thing over and over. I also enjoyed the actual graduation of the senior players. It was extremely heartwarming. There was more than one tear that came to my eye.
If you watched the drama, then you should watch this. It won't give you a ton of closure, but you will get some. However, if the drama wasn't your cup of tea, then you should be fine skipping this entirely.