I can't say I'm completely satisfied with this film. It is a bit uneven. Certainly better than the previous two entries, but nowhere as balanced the first two. It is both more serious and also more fun. At the same time. One the one hand you have some strong violence (for a movie like this) on the other hand it has more humour as well. I'm not sure if the combination works. For every thought-out nuance comes a cheesy line. And it's a pity, because when Singer was directing it seemed better handled.
The cast is definitely a big help here. Well, most of it. James McAvoy and Michael Fassbender do their character's justice, which is a feat in itself for their following Stewart's and McKellen's footsteps. Both Xavier and Magneto have and arc in the film and their conflict is a little bit more personal than the two old veteran actors exchanging quotes in a Shakespearan way. Believe it or not, but these characters are even richer than before. That's a good thing about the film. But, still, it is rushed, as it the whole film. There are so many elements in it that some of them are sacrificed. Like Emmma Frost, for example. She doesn't do much in the film and a typically stiff performace by January Jones doens't help. She's perfect for Betty in Mad Men, but I don't buy her in any other role. The younger actors are all fine. Kavin Bacon plays a Bond-type of villain. Quite literally and he's really good at it.
The most irritating thing about these kinds of films is that they try so hard to make us buy this world they're creating, to make it as real as possible that the signature key elements from the comic books (like superhero costumes, nicknames) sometimes completely take me out of the picture. It's like The Dark Knight which is a pretty strong thriller, but there is guy in a bat-suit, for some reason. It's Richard Donner's Superman, which created a world around that doesn't make the hero silly. These days, everything must be "psychologically complex" and "real world". I'm not sure how people with silly nicknames and outfits fit into all that. But it's a minor quibble.
They worked hard to make as many in-jokes and references as possible. So you get a surprising cameos from two actors from the other films (
Still, I can't say it is bad. Neither is it good. Most of the stuff works. But I probably won't be seeing it again. The score is disappointing and it's not about the guitars at all. They help to create the expionage genre feeling (James Bond again). But it is completely unmemorable. Which shouldn't surprise me these days.
But I'm sure most people will like it, so don't worry. It's a safe option. But don't expect to be blown away with wit and good taste.