Ok, I already own an M3. I got this almost 2 years ago. Right now, I'm considering R4, I don't know whether it's worth it if I already own an M3. I don't have a pass card for the M3 though. I originally bought it for GBA homebrew and DS wasjust starting up. Although it does play DS. I heard R4 only uses micro SD? Is there a version that supports regular SD cards? I really don't feel like buying more memory cards. Also, is there software for writing on the DS? I just want to write (or type) into it, save it as a file, and then transfer it into my computer when I get home. A laptop costs too much just for writing on the go.