It's not as good as Aria the Scarlet Ammo. The characters are funny and it's not a harem show, thank goodness, but the plot's lightweight and the last few episodes' action finale needs you to ignore logic.
Firstly, the set-up. The cast are all gun-toting "butei" action heroes at Butei Training School, where the uniforms are bulletproof and so you can get in blazing gunfights and fill the air with bullets. This appears to be considered more or less safe, even though the girls wear short skirts. Bare legs, unprotected heads and hands... I'd guess that nearly 50% of their bodies are vulnerable. This was just as silly in the 2011 series, but there they got away with it because everything seemed to be one-on-one duels between acrobatic girl-commandos with superpowers.
Here, though, ep.12 has the girls fighting someone in powered combat armour... except that this is a lot like Ripley's exosuit cargo-loader in Aliens, i.e. it wouldn't protect you against bullets. This armour's pilot is a girl who's wearing nothing on her legs. Our crack super-agent heroines shoot at her a lot, but their bullets all bounce harmlessly off the metal.
Why don't they aim for the flesh? If they're just trying to hit the armour, why bother shooting in the first place? Come to think of it, how unlikely is it that you can fill the air with lead and never happen to hit large vulnerable areas?
That's happening all the time on this show, admittedly. It's just that ep.12 is forcing the stupidity even further down our throats, since Power Armour Girl doesn't move or dodge. She just stands there. She shoots the hell out of our heroines and they keep letting her do it. I don't mind silliness and absurdity in themselves, but here it's undermining the show's finale. Aria and Akari could have defeated their enemy at any time. One bullet. Bang. Dead baddie. If you choose to believe that they're deliberately holding back and being noble (which would admittedly be in-character for Akari), then presumably they don't think the situation's too serious. If they don't, then we don't either.
Oh, and Akari seems remarkably unconcerned about getting that antidote for her dying sister. She almost seems to forget about it. Ep.11's baddie was more convincing, though, with poison attacks and a personal vendetta against Akari.
The 2011 show had better villains and a less throwaway plot. It also had the whole thing of making everyone the descendant of some famous hero, which was both cool in itself and providing a helpful distance from sanity that helped one buy all the rest of the absurdity. This show, though, is mostly just character comedy. I like it. It's fun. However it goes downhill when the villains show up, which isn't what you want in a show like this. The characters also lack the bite of, say, the Kinji-Aria sparring, although they make up for it in other deranged ways.
That said, though, I still enjoyed it. The plot's holed below the waterline and the action scenes are fantasy gun battles, but the cast entertained me. Even when it's just comedy filler, it's good filler. Aria-Akira give the show a relatively serious core, since Akira's dead set on wanting to be Aria's Amica, but Aria's reservations are well-founded and played out properly over the course of the full season. (The Amica system involves an older student adopting a younger student and becoming their mentor and combat partner for a year.) Then around them we have the other nutjobs, with three pyscho lesbian stalkers (if you count Shirayuki's cameos from the parent show) and their bizarre rivalries and alliances. Eventually it's almost as if the show's setting up a Shino-Takachiko romance, except that the thing they're bonding over is their race to be the first with Akira.
Oh, and there's also the massively in-denial Raika getting a wife and an underage harem.
What interests me about this is that it's a lot like standard harem comedy, but without the 2011 show's harem framework. Kinji shows up occasionally, as do all the parent show's regulars (plus one light novel character who didn't make it into the anime), but those are basically cameos. Aria's the one crossover regular. Apart from that, everyone's new... and they're: (a) all girls, and (b) the romantic attentions are more spread around. You'd think Butei Training School had gone single-sex. This makes the show far more palatable. Even when they're still basically the same jokes, it's less eye-rolling because it's not making one male protagonist look like the sole object of desire of all girls in the universe.
Also, more fundamentally, I like them. Everyone's lovable, even the goofy psycho stalkers. I also like the show's egalitarian attitude. Anyone can earn the right to be treated the same as a veteran if they can prove themselves good enough. The show's farcically unrealistic, but... well, it's Aria the Scarlet Ammo. I'd already accepted sillier in this fictional universe before I started ep.1. This is a throwaway show, but despite some hiccups I enjoyed it.