[SIZE=2]The main difference is the fact that all of the third-party cards (i.e. not actually manufactured by Sony) are unlicensed and so are not neccessarily up to the same standards Sony has.While they may be a few dollars more I would definitely suggest buying the actual Sony cards-if you think you would need it I'd suggest buying the twin pack (in case you have more than one person playing the system in the house and avoid any mishaps with overwriting game saves).[/SIZE]