I beat the game 100% and I will tell you this, for me Sandy was very predictable unlike Suki and Crystal, I never used the cameras, aside from the music box, the reason is, because they are so fast, milkmean can ruin your run when you shut the door to early and the last character (I can't remember their name at the top of my head) isn't really a threat to me and I'm not gonna lie it's quite the challenge because sometimes they attack you at the same time