And I was sucked in immediately. The first chapter moved lightning fast and I was confused at where the story was going. It started out very shoujo and embarrassing, but then it took off! I thought it was more than just your average shoujo (aside from the heroine - she improved a bit as the story progressed, but she was a boring typical cliche lead, imo).
Anyway, other jumbled thoughts I'm just going to spit out:
 First, I need to admit that I'm a sucker for time travel. You say time travel and I'm there. So I'm a bit biased based on that alone.
In terms of characters, I really didn't like Hiroto. I recognize that he had a bad family situation, but his personality - blegh. Selfish dude.
On the other hand, Tsukasa is the ultimate perfect male lead - easily embarrassed, caring, selfless, devoted. Every scene with him made me smile. I'm so done with playboy characters so he was refreshing.
Hana was awesome. She and I would be great friends in real life due to shared interests. Hah.
I didn't realize this manga would go into some slightly darker territory. Obviously, it's still happy overall, but it was a change of pace that I don't see enough in romance.
This manga made me think of Orange (TAKANO Ichigo). They are very different, but this had some similar threads.
So this was ADDICTING. I stayed up until 4:30am to read this and I had work at 9am. Highly recommend, especially if you like school life shoujo, but you've read 50 of those and you want something with a twist.