The actors who played the leads were good, but they changed the original story so much that it detracted from the story. They took away Kaneda's spunk and made strange, and took away Yanase's sense of humor and made him more boring. They also created unnecessary angst that was not in the manga. The couple in the manga had a sex life, in the series they barely kissed.

In the manga, Kaneda moved to Canada to be with Yanase, and returned to Japan when his year was over, 3 months after Yanase. That guy did not come from Canada to mess with Jun. Once they confessed, they were lovey-dovey.

I recommend only reading the manga, or reading the manga after watching the series. I was unable to appreciate the series because I read the manga first a few years ago.