I think this one is definitely a readable and good one, art- and story-wise.
I do agree with the guys that it is typical and cliched. But I like its execution. Only problem is how rushed, despite making senses, it is towards the end. And I definitely don't like how usually, not just this but shoujo in common, elaborations on the guys' feeling are missing. I am pretty sure Shishio was devastated. And I am confused on how unconditional Mamura has been.
I don't dislike the female lead that bad, she was inexperienced for God's sake. It is just the choice of the author. She can try to make it work out for Shishio and Chunchun. But it can be the other way because somehow it seems more appropriate and approvable socially speaking. So somehow it is realistic to me.
But then I just feel damn sad for Shishio. I truly do. I think Mamura is nice and all. But its just the struggles Shishio bears. It hurts for both him and Suzuma. Mamura is the better person. But I still feel incredibly sad for Shishio. So so sad...
[2016 Update] Although I'm still sad, I'm a bit lightened up that I can re-read it sometimes. After a bit of conflict and personal deliberation, I thought the ending was for the best. I am still sad though. But I like the series as it is. Maybe a bit better for Shishio, please!
[2019 Update] Damn, I'm still super upset for Shishio's treatment from the author! She makes a side story pairing him with the manga editor girl which was too fast too furious. It leads nowhere. Then she makes another chapter further exploring their relationship. And the manga editor, to me, is too similar to Suzume... and more: nonchalant, stoned-face, have certain quirks, surpressive (in term of personal feelings and emotions in contrast to Shishio's extrovert appeals), blunt (can say things straight forward which is opposite of Shishio's downplaying his chains of thoughts). Still horrible treatments till the... extension. I'm down-grading this from 9 to 8.5.
As for Mamura, he still aces it all, haha. Like he is still sharp, honest, sometimes self-enduring because he gets too deep with his thinking and worrying about Suzume. But he says it and he shows it. So, of course they are still going strong.
There's a side story called "Cookie Girl Cream Boy" I just saw. It's a real Oreo treat for all. It's good, much better than enduring the pain caused by Shishio - Suzume - Mamura's love triangle. (So much pain for Shishio's part - although I'm all for Mamura, I can't help feeling so sad for the "Ryuusei" of the manga title - that when I re-read, I only read from chapter 52 or so onward.