I'll be honest here, I was a little girl when I read this series - but I can still remember it very clearly. Psychic twins who try to keep their classmates - or peers, in general, including faculty - from knowing their secret? I still haven't seen or read an anime/manga with a storyline like that - feel free to point one out to me.
The story is a good one. When I was reading it, I couldn't get enough. You won't believe how much money I spent on the volumes when Tokyopop was still releasing manga. In fact, I believe they're still laying around somewhere in my bedroom back home.
The art, on the other hand, not as good as the story. It might have been better if someone else illustrated it - but that's all I can say on that.
Characters are pretty good. Mika was always my favorite while I was reading it, followed by Toni. Then there's Yuuya Noda - Jackson Neil, for people reading the English version - who was the only male character I liked in the whole series. I didn't really care much for the other characters.
I enjoyed this series very much, but it could have been better. (The low enjoyment rating is because I can't even finish a full volume when I re-read.)
Overall, it's a good series...when you're 8, but it is geared towards ages 7 & up, so no surprise there.