Thanks for the links, PsychoticX and truehappiness! Sakuranbo seems more similar to the first track than the second. It's very upsetting to find this out
I don't get the Will comparison... is it the Miyuki Nakajima song alone? It sounds very different from Will.
Edit: Oh, I found it. truehappiness, the link is another one on the site
Hmm, similar structures. But not an exact copy. I'll have to give it more of a listen. This is the proper link:
http://fish.kakiko.com/toutsukai/63.swf
Some of the "ripoffs" on the site are ridiculous. The Kasou (Ai Otsuka)/Skirt (Chara) comparison is definitely tone-deaf.