get M3 SAKURA 1.35X GU4.3C (USA/Europe), it is actually a dual boot of Sakura and Touchpod (the old/original M3 Real firmware). Unpack it, and put the System folder in the root of your card. Create a folder named NDS in the root of your card, that's where commercial ROMs go, might want to create a Picture, Video, and Music folder in the root too in case you ever want to put any of those in...
the first time you boot, it will show u both OS, Sakura and Touchpod, pick Sakura and it will automatically boot Sakura from then on...if you ever for whatever reason want to switch to Touchpod or vice versa, after turning on the DS, hold A and it will bring you to the OS selection screen...(although you should just stick with Sakura)