I just bought two 8Mb memory cards (they come in twos, a blue and a red), and the game is recognizing them, but recognizing them only as unformatted. I bought these thinking that there were plug and play, and the guy who sold them to me told them that all you had to do was throw it in the slot, and games would save. WTF am I missing here????
"You know Monsoon, I am impressed, and I don't impress easy" -Jesse "The Body" Ventura
You may want to try GameFly.com to rent them first. This is the only place I know of where you can rent a GBA game. I've regretted a few $20 purchases in my time. Final Fantasy Tactics has kept my wife very busy.