I usually give one to my brother. But before I do, I usually mine it for starters. E.g., if I choose Chespin on X, I'll get Fennekin on Y, play far enough on Y to be able to trade, trade Fennekin over, start over, do the same thing with Froakkie.
Also this time, I'll be able to give myself multiple event Torchic with mega stones. Once I think I have enough, I'll reset the card, and give it to my brother.
i buy both so i can always restart one and keep all my pokemon/items on my other file. then later after i get the next games the coming year i give the restart file away to a friend who cant afford games.
XBL GT: A Bit Of Charm, 3DS FC: 3668-7321-0017 Games Currently awaiting: Darksouls 2, Pokemon X/Y, Super smash bros WiiU