I think I agree with Krelbit on this one, It's much easier to gain 2 hearts and level the Eevee up yourself then to trade it with someone, wait for them to do all that, then trade the newly evolved Sylveon back. I find it enjoyable, really, to play with my Pokemon in Poke-Amie, especially when they copy your faces and smile at you! That's my opinion, anyways.