misono... Girl, no.
I like misono but that cover wasn't pleasant to listen to.
This is honestly like news to me how "iconic" Ai no Uta is in Japan. Many people cover it, and kuu always performing it gives me that impression. I've always loved the song, but I don't remember hearing much of the song's impact around the time of its release, but I guess I'd have to be in Japan to have really seen it.