As a child, I just ever-so-slightly preferred Kate, because her ever-changing hair was so fascinating, and she provided us with all those songs. Now, however, I'm not sure: Mary has such a lovely personality, and she has a nicer speaking voice than Kate. Ultimately, the ladies are, of course, about equal. I'm very fond of them both; they're definitely in my top 5 list of characters, albeit not quite in the top 3.Alternatively, you could ask who is preferable, Zelda or Cystar? I say Cystar, any day! All the "wonderful"s in her speech may get just a tad tiresome, but I have to sympathise, because I remember 2 of my male friends at university got sick of me using the word "cute" too frequently.