I don't care for her. (meaning I don't hate or like her)
Sometimes I like her voice and sometimes I really dislike it. (I liked her in the preformance of Dekiru Onna, in the Sexy 8 Beat concert)
I'm not trying to be mean, I hate "haters" just as much as anyone else
I don't think any member deserves to have haters. You're probably right that Aika is one of the members with most, but I think it's about even in general when it comes to haters of different members. Aika is the new girl, which makes her a general target of hate. Since then people can complain about why she was chosen and not their fave girl from the audition, which is unfair to Aika. She's not the best singer, but she has time to improve if she really wants to. So let time show what kind of girl Aika will turn out to be.