It's a bit silly. It's a magical girl show with all the traditional genre trappings... except that it's trying to be realistic and SF. But with dumb plot points, fanservice and a director who really loves close-ups of arses.
Our idiot schoolgirl heroine is Akane Isshiki and she does newspaper deliveries every morning on her Look At My Arse hoverbike. (Probably not its real name.) A few years ago, her grandad invented the Manifestation Engine, a machine that now powers the world with unlimited free energy. Awesome... but, despite this, the world hasn't really changed much. No one's redesigned civilisation or the world economy, or even invented much.
Now, though, grandad's about to be turned into a talking animal, while Akane and her colour-coded schoolgirl friends will fight a civilisation-threatening monster (called an Alone) every week.
It's sort of likeable, in a generic magical girl way. The Power of Friendship is implied to be a power greater than all others, for instance, even if your enemy is capable of destroying the universe. The personalities are familiar, so for instance Akane (red) is the childish idiot heroine, the blue girl is the serene best friend, etc. It's so slavish to its genre that I wonder why they even bothered with SF trappings.
1. FANSERVICE. The arse close-ups and those school shorts are both fairly tiresome. Is that their school uniform? It seems to be, but a real school uniform surely wouldn't show your arse cheeks? Meanwhile, the girls' not-magic weapon names almost all start with the word "Naked", while their power-up transformation is called "docking" and involves two naked girls getting so intimate that they enter each other and merge into one body.
(There are two versions of all this. Crunchyroll has the censored TV episodes, but the Blu-rays have nipples.)
2. It can also be dumb or eye-rolling.
The green magical girl (Wakaba Saegusa) is painfully stupid in ep.3, her debut episode and the only one to give her a personality, Thereafter, she's just another generic team member, although she does get some downtime in ep.9. Anyway, she's studying kendo in the Tengen Rishin style, but she doesn't seem to understand the concept of competitive sports. She thinks losing a match is a disgrace to her kendo school. IQ drops like a stone in anyone who's standing in her vicinity, e.g. the girls getting ordered not to let anyone know about their transformations. Sigh. Or, in other words, piss off. (Akane's attempts at this are, uh, inconsistent.)
Grandad has designed "docking" only to work with Akane. When she gets hospitalised, the other girls can't transform into their Vivid forms and so they nearly lose a battle.
Goofiest of all, though, is ep.10. There's a Dark Magical Girl (of course) who befriends our heroines in their civilian forms (of course). No one knows that they're enemies on the battlefield. When all is eventually found out, the Dark Magical Girl's reaction to this is so dumb that you'll howl with laughter. Why's the openly evil girl acting all betrayed, eh? Admittedly the "liars" accusation is completely true (although the girls don't realise), thanks to those "don't tell anyone" orders. However that cuts both ways, with a certain amount of "pot calling the kettle black" from the girl who'd been summoning conventionally indestructible monsters that killed lots of soldiers and pilots while trying to smash the world's energy supply.
Ep.12 is almost as dumb, but less funny. A mega-Alone is trying to destroy the world. It's undoubtedly powerful enough to achieve this and it's been flamboyantly killing the conventional armed forces who get pointlessly thrown in its direction. We've known since ep.1 that only magical girls can fight an Alone... but everyone keeps faffing around and dithering, instead of just sending out the girls immediately. You'll be headbanging. When Akane eventually suggests that she and her friends go off to fight, grandad says it's too dangerous. Uh, grandad? The alternative is world destruction.
I liked the yellow girl (Himawari Shinomiya) and her classroom robot. The show has a heart when it comes to the Dark Magical Girl, if you can accept stupid astonishment at the most obvious, inevitable things. Otherwise, though... naaaah. It's contrived. The show's just not very good. At its best, it's a generic magical girl show with no surprises but at least a decent level of emotional engagement. Underneath that, though, its issues make it unconvincing, cheesy and lazy.