This is a reminder to those in the US to download your Heracross/Pinsir from the Internet. Also, you can pick up the Megastone from your local Gamestop.
However, keep in mind, some GameStops are forcing people to preorder Pokemon AS/OR to get the code. According to the Nintendo website, you DON'T have to preorder the game to get the code. The preorder bonus is only the poster, not the code.