When info on the adapter was originally released, i was excited, until i realized that if SD cards functioned exactly as memory cards, Nintendo would risk cannibalizing their own memory card sales. i don't feel like looking up the specs of GC cards, but SD cards, even the small 32MB cards, held several times more data at merely twice (possibly less now) the price. Profit margins are high on accessories, and Nintendo would've been foolish to allow the adapter to function like this.