Darkflame Shyvana - Love spell effects, and dark look compared to other skins. Great details.
Blackthorn Morgana - Great detail, high poly count, nice upgraded look for the character.
Arcade Sona - Spell effects, sounds, great high poly count model..just all sorts of great features.
Soul Reaver Draven - Love skins that make the champ look drasticly different, and the voice effect is nice touch. I don't like default at all, but I love Soul Reaver.
Pulsefire Ezreal - Great skin, amazing effects and details, but I feel his model size is a but odd in comparison to other human characters. (Have you ever compared his head to MFs, or Graves, or any human.)