As a standalone film it might work, as a Batman / Superman Film it is garbage

Rating: 1/10 (12 August 2016)

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Let me start this off by saying I am a huge fan of DC Comics & have some knowledge of the DC Universe. My opinions are based upon this and not ONLY the films that have been released over the past two decades.
Lets start with the basics:
Superman: The boy scout, the paragon of virtue and the living embodiment of morality. Has Superhuman strength / speed / vision / hearing / lazer eye beams / flight / cold breath / nigh invincible
Batman: Greatest detective alive, works towards peace and order. Has tons of money / lots of gadgets / martial arts trains / clever fella.
One important thing to note... neither Batman nor Superman kill anyone... ever. Accidental deaths (and pre 1990's batman) aren't included in this.
However, and this is the premise for the entire movie, is that if Batman considers that there is even a 1% chance that Superman MIGHT one day decide to take over the human race, then he must be killed no matter what. This is in direct contradiction to everything we know about Batman. Lets for instance take the movie at face value and that should someone even have the remote possibility of becoming a tyrant, Batman will kill them... why hasn't he killed: Warlords, Dictators, other Superheroes but most importantly... the Villains he fights (i.e. Joker)? If we were to accept this batman, well he wouldn't be batman, he'd be Punisher with a bigger budget.
For the purpose of this review Im going to completely ignore the fact that if it came to a "fist fight" (as depicted in this movie) between the two, well its not even funny how badly Supe would win (faster than the speed of sound coupled with flight and super speed vs a dude in armour...). If there are any clever fella's out there who wish to argue that Batman could win, watch Justice Leauge: DOOM to see how he actually would do it. He uses brains not fists.
Also the character of Batman (and in no way was Ben Affleck a good choice for the role especially after what he did to DareDevil) was horrifically bad. As Bruce Wayne he was a tool & lacked the suave sophistication we've come to know and love from him. As Batman, he killed a ton of people in the movie (saving Supe's mother dearest), which again goes back to... Batman don't kill (otherwise he'd be as bad as those he fights - yes hes a complicated fella - and he cant ever allow himself to kill otherwise he'd never stop killing those he feels deserves it, watch Batman: Under the Red Hood). Oh and when he find out Supes mummys name is the same as his mummys, SUDDENLY "lets be friends and work together to stop Luther/ save mummy"... like they couldn't have done that in the first instance.
Batman Side Note: Ben was a little too "buff" for the role, Batman isn't built like a tank, hes a martial artist... not an MMA heavyweight (not to mention the ridiculous montage of him lifting weights and tyres... hes a billionaire for crying out loud, I think we can assume he has a gym in one of his many rooms IN HIS MANSION).
Superman, just so happens to concede to Luthers plan to have a gladiatorial match with Bat's to save his mummy. Superman can simply use his extrasensory superpowers to find his mummy (x-ray vision, super hearing etc...) at super-speed within the 1 hour allotted time slot.
OK so we've covered why Bats vs Supes is just a dumb concept (if anything it would be Supes going after Bats for going too far, not the other way around & then a movie about Bats running and trapping Supes in various ingenious ways using Kyrptonite to escape him etc..).
NOW its not over, we have the second (or third however you'd like to look at it) "story" - Wonderwoman. Gal Gadot is a 5ft 8 skinny model that a strong wind could knock over. Now depending on which wonderwoman you'd like to cite, I think we can agree that as "Princess of the Amazons" you'd expect her to be more "amazon" like i.e. 6ft plus with a stronger build (at least some meat on her if not defined muscle (you can be defined without looking like a bodybuilder)). The casting was awful for this, Gal might be a good actress I don't presume to know her work, but the choice was on par with Ryan Renolds as Green Lanter, Ben Affleck as DareDevil and George Clooney as Batman (good actors, terrible choices for the roles).
Also Luthor creating, by mixing his blood with General Zod's, Doomsday hurts my head so Im not even going to bother commenting on what an awful idea that was (also means you'll never see a SuperBoy... half krypton half human).
In short... this was a mish-mash of a movie that tried to tie in several different stories and introduce several characters for the future, but ultimately failed in pretty much every way especially in casting, concept & story line.

Edit, I've used DC animated film references as you should all watch those instead of this trash (and if you don't want to read the comics.... which get complicated depending on author / timeline / multiverse etc...).