X-Men Days of Future Past is Neither the Best, Nor the Worst 'X' Film to Date - It Falls Somewhere in the Middle
As always, my reviews are mostly spoiler free, however with X-Men: Days of Future Past, I feel I have to give away some very minor details in order to make my review more coherent.
I do not count Days of Future Past to be among the best X-Men movies, nor do I really count it among the worst of the X-Men movies, rather I consider it to be somewhere in the middle of the pack. Better than such films as X-Men: The Last Stand, and X-Men Origins: Wolverine, but not as good as others, like X-Men, or X-Men United.
I had some high hopes for this film. Director Bryan Singer, who made some of the best films in the series, was back at the helm, but Singer is only one piece of the puzzle. The reason the first two films worked so well, was the synergy between director Singer, and screenwriter David Hayter. But David Hayter wasn't the screenwriter this time, Simon Kinberg was - and Kinberg is the screenwriter who previously wrote the script for X-Men: The Last Stand, one of the worst films in the series.
So not only is the Singer/Hayter dynamic not in play, Singer actually has to deal with a script that is full of stuff that just doesn't make sense. Just a few random examples include (and here's where some minor SPOILERS come into play): at one point the power in cerebro goes out, yet Beast walks out the automatic door, no problem to go turn the generator back on (sure it could have been on a separate power source, but it would have been so much better if he had had to pry open the door), in another scene Magneto pulls Mystique to him by a bullet in her leg - this is utterly ridiculous, as any strong magnetic force acting on a bullet like that would just cause the bullet to be torn from the flesh rather than drag the person with it. And that's not the only ridiculous use of Magneto's powers. At one point he actually infuses the Sentinels with metal parts so that he can control them - which would be fine if he controlled them like puppets, but instead, he somehow has instantaneously reprogrammed them, computer genius that he is, with the force of his mind. Professor X's powers are similarly misused, at one point he 'stops time', which would be fine if he was just mentally immobilizing people, like we know he can, but he completely immobilized people who were falling in defiance of gravity!
Another area where the film fails is in its attempt to maintain continuity with past films, but even here it fails, as Magneto mentions at one point that Angel is dead (in the past, after the events of X-Men: First Class), yet we know this isn't true as he appears in X-Men: The Last Stand.
So, while Bryan Singer does a very good job of maintaining the 'human-ness' of the story, it's definitely hampered by the writing. Even where changes from the comic made some sense - Wolverine is the time traveler here, not Kitty, which makes some sense, given his mutant healing power and the related fact that he doesn't seem to age - it really doesn't serve to move the series ahead much, as once again all the attention seems to be focused on Xavier, Magneto and Wolverine, all of whom have already had more than their fair share of screen time in past films, to the detriment of such under-explored characters as Storm, Nightcrawler (who's been pretty much written out by this point), Rogue, Colossus, etc.
It's still a fun summer film, and one which actually uses the current 3D fad to pretty good advantage. But, on the other hand, at this point it seems the series has really sunk into standard superhero movie fare, which is fine, but a bit of a disappointment given that it was the first (and for a long time the only) really good superhero 'team' movie series.