
It was worth the $5 I paid to have a go-to for when I find myself in waiting rooms, but I find it too easy and not particularly interesting after about the third or fourth playthrough when I unlocked everything, and I've since beaten this thing one-hundred or so freaking times, but more cause I'm bored and broke than that it's that great. I think it's ok, and it has enough content, including the option to play as Tails and pick between Japanese and American soundtracks, but I'm not suggesting you go out of your way or anything.
As for Hillary Duff, yeah, that's one of the ones in that list I never listened to, but I at least know who that is, unlike with Diana King. I can't judge your sister though, I liked Avril Lavigne's singles when I was a kid.