Lance might be a b*da*s and a dragon master, but Blue is my favorite Champ, not only between these two, but in general.
What i loved about RBY was the fact that your Rival was really pushing your buttons and laughing at you every step of the way. When you finally beat Lance and his Dragonite, you then find out there is a last hurdle between you and being the Champ: Your freaking Rival!!
It might have been the fact that i was a little kid, but to me, no other Champ Battle can match this kind of epicness