Story : 6/10
While watching I was constantly thinking about the multiple ways the story could have been better presented. The main problem of the said story is Mayuri. All of the movies intrigue is based on Mayuri (thus the title), leaving the first 35 minutes literally only fan service, which I don't mind. Reviewing the story more would be major spoilers, which is the problem, since you can resume the story in a sentence. I can't be to nitpicky about the story since it is Date a Live after all, and good story is not the top priority I watched this.
Art : 7/10
Honestly, for a 2015 movie (released JP), it looks bad. The art style remains, but it feels like all the time they used to make the movie was pointless. This is maybe affected by the quality that I was watching the movie in, but the fight scenes all seem rushed, and not a single pause looks good in the fights.
The good side are the parts that were not rushed were all well drawn and animated, and had the iconic Hyperdimension Neptunia/DaL/Fairy Fencer F art style.
Sound : 8/10
Nothing remarkable, nothing bad. The movie did lack some ambient sound sometimes, but it was on rare occasions. The voice acting is all well and good, as it was in the anime.
Characters : 8/10
This is the most subjective mark that this movie can get. You either give a 1/10, a 5/10, or for Tohka fans, an 8/10. One might say that no character development, but why develop characters who are already fully developed, just like in all anime adapted movies. I already addressed the Mayuri problem in the story part of the review, I can only see Mayuri as a story engine, and not a real character.
[POTENTIAL SPOILER] Why the high mark? Well, the main reason is Tohka. The movie gave all the girls their moments, but mainly focuses on Tohka. Since I am a huge fan of Tohka, I liked that a lot. She is the only one that gets wrapped by the story like Mayuri, she is the only one who get's the super transformation and she gets the most attention from Shidou. So if you are an Origami fan, or a Mana fan, this mark will be super low.
Enjoyment : 6/10
It's not that I didn't like the movie, I found it empty. The ending was one of those "one more season maybe?" things, which to be honest may be a possibility (YuruYuri case getting S1, S2, Movie, S3.) I feel like I missed out on the light novels, which surely were a lot better developed. There is still Kurumi who remains a giant mystery. If the movie would follow the Kurumi story from the 2nd season OVA, it would be a lot better. I went in watching without knowing what to expect, an "OVA" type movie, or large story progression just like the Love Live! movie. What I got is a mix of 2, which was honestly meh.
Overall : 7/10
Date a Live : Mayuri Judgement is not a bad movie, it just lacks the "punch" and the remarkable moments to make it good. If you are a big Date a Live fan, you will surely like this.
