Every incarnation of the Cloud Kicker and Merry May model! (Not including errors such as different eye colors or mismatched cutie marks.)
This model doesn't seem as popular as some others. Both the Lyra and Bonbon colored Pegasi use this one, though, which I thought was neat.
Lily is rather unique in that she is the only Earth Pony with this model. (Rose is the same way with the Lyra/Amethyst Star model.)
AI Download: [link]