It's much better - and much worse - than the numbers tell.
The opening scene with the babies almost had me turn it off. It was just stupid. Then the movie turned, and for the most part, it was pretty good.
I don't think I've ever seen Ezra Miller before. I know the name from the insane press he's gotten, but was never really inclined to see his films. I think he did a great job playing both Barry characters, who were so different from each other. Too bad his career is likely over.
The movie just tries too hard. Some of the CGI is really bad. I think X-Men did the speed thing better with just a 30 second clip of Quicksilver than anything this film accomplished.
I think it could be trimmed down, and fixed up with just small tweaks, and they'd have a much better movie. As it stands, it's good enough.