I had a lot of fun picking the colors for these. Went off the cutie mark colors as inspiration. I know, not sure who my favorite is, it's a toss up between ZappleJack (which someone pointed out that it can be read as Zap Apple Jack) and Zainbow Dash. Zuttershy comes in close to.
Zainbow Dash is on HOLD. Zutterfly , Zapplejack and Zwilight Sparkle are still avialable with FREE shipping.