I'm putting 5 stars because that's what I put for books I have truly enjoyed reading and would read again. 
I'm not saying that this book is perfect, but I like that it got me questioning, sometimes agreeing with one side, sometimes with the other, sometimes leaving me not knowing what to think. 
I couldn't put the book down. The story was gripping, and sometimes very intense, a real page turner. I don't know if I'm really into the dystopian genre, but as a feminist I was excited to read this. 

I like that the characters are deeply flawed therefore deeply human. Let's take Miranda, the main character. At times, yes, she is frustrating because she doesn't get the need for feminism, was a kept woman and because she understands why Nick did what he did. But at times she is also angry at him and at men, she is not completely blind. She has a very moderate point of view when it comes to feminism, it's true, but surprise surprise, it's still the case of many women nowadays. A lot of them don't really have problems with men, or they roll their eyes playfully at them and their antics, without thinking much about it. They know there is violence against women, including sexual, but they don't see it as being spread in the whole world. They don't get it, as Win would say. Maybe they're blind or society (men?) made them blind, maybe they're not educated enough, maybe they think it's normal ("hardwired"), maybe they accept their situation and are happy with it (what's wrong with being a kept woman if you enjoy it?). But these women exist, and there are many of them. 
Also, can you really blame Miranda for her difficult relationship with feminism/her mother, when

her mother killed her father who yes was a shitty husband but a good father? When she has seen her mother's view distort the world and causing pain, like the innocent employee tying Miranda's shoe turned into a pedophile for her profit?

 
Win too is a complicated character. Yes her view of the world is extreme and raises issues. But I also understand why she

murdered her husband. You sometimes hear that kind of stories, of women who were abused over and over and ended up snapping and killing their husbands. Who can blame them?

When you start really going into feminism, truly look at the numbers, at all the violence men cause women... Yes, I believe a part of you end up hating men a little. It's overwhelming, it's scary. And it can be difficult to find good men. You may start to think that a society without them would be better. I am not saying that's what I think, but that I understand how Win may have gone there. And why some (non fictional) women would think this way, too. 

Contrary to what some people wrote in the reviews, I don't think that the author's point was to say "boo extreme feminism is bad!" or that "men are good, poor men, mean women". I honestly think Christina Dalcher wanted to question what kind of world is possible, what we want, how far we would go in our thinking. 
I do agree with people saying that the "big" twist was a bit predictable, but I still think that it is worth a read. Be mindful of the content warnings, though.

About the epilogue:

I've read some reviews and I guess we see it differently. I do agree with the fact that it felt rushed. But I don't think the idea was to say "we are bound to act like this according to our gender", to me it felt more like a question: was re-integrating men the solution? Did they ruin Femlandia, turning it into Landia? Even if treating boys like this was awful, wasn't it better for women? 
As we got closer to the ending, I imagined something like just a few years later. With boys reintroduced in the society, turning into teenagers then men, would violence and sexual assault against women happen again? And how would that be handled by the society? 
Alternatively I imagined the boys/teenagers/men living within Femlandia, but being second-class citizens, at least for the next generations as they would still be wary of men. But this could have carried on, just like in our world women have been treated as second-class citizens for generations/centuries.