I have 2 3DS one of which I will use only for loading backups with gateway, it's the first model so it came with a 2Gb SD card and I think it won't be enough given the fact that I'll need 1Gb or so for emunand and I heard that Smash Bros requieres at least a 4Gb card, do you think an 8Gb card would be enough? which retail games require space on the SD card besides Smash Bros?