Oooh this is really hard! I don't think I could ever get rid of Tink-a-Tink-a-Too, who was the first pony I ever got as a kid, and I love her to death. I still remember picking her out at the store, and she was usually the star of all of my games with my ponies. But my G1 Milky Way (my first G1) is also really, really special to me. I've only had her for about a year, but I absolutely adore her and I associate her with some really good things. She came in the mail the day I was presented with an award, so I always think of her in relation to that. I'm not sure I could pick between the two of them, as they are my favorites, but I've had Tink-a-Tink-a-Too for something like 10 or more years now, so I think she would win out even though I would be absolutely crushed to lose Milky Way.