Whether or not you like this series depends on your tastes, I happened to enjoy reading it, but I'm sure (as can be seen from the other comments) that there are plenty of people who won't enjoy it. The manga revolves a lot around the growth of the protagonist as she matures and tries to deal with her own insecurities while also trying to figure out what it is that she wants out of life (since her dreams of being an idol are now dead). I would say that this manga's a bit different from other yuri mangas (at least the ones i've read so far) in that it delves more deeply into the main character's orientation and the issues that result from her confusion, uncertainty, and curiosity in that regard. It's a serious manga, there's very little humor, if any. I found myself confused at times because it wasn't clear what's motivating characters to act the way they do until things get explained later down the line. But then again, people rarely fully understand their own actions, and that's just another thing that I think makes this manga a bit unique, as the reader is left wondering what the characters are thinking at times. Personally, it annoyed me a bit while I was reading it, but looking back now, I actually appreciate that aspect of the manga not only because it's unique but also because it's more of a reflection of real life, where you're left guessing what other people are thinking (though the manga doesn't leave you completely in the dark). Oh yeah, just a note, currently, CH34 is the most recent release (a little bit of a spoiler ahead). From what's happened so far, this manga is also unique in that everybody doesn't just accept the lesbian couple, an issue that would most certainly arise in real life, although I'm disappointed by the fact that, as of yet, the parents aren't aware of it (I've only read a couple of manga where the parental issue is actually dealt with in some way, shape or form, and even then, i've never read one where it's fully dealt with), although there's still that possibility since the manga's still ongoing.
Perhaps my only true criticism is that it's a bit too drama-oriented, in that it tries too hard to create issues, and at times it comes across as forced. Yes, Yukino and Setsuko are a bit insecure in their relationship, but I don't think that means that they're going to fight or get jealous anytime one of them spends time with someone else. Or how (slight spoiler, I suppose) people with feelings for Yukino just suddenly start popping up out of the ground.