Personally think M3 perfect is nice and i use it myself. i do have ez4 deluxe and supercard lite but i perfer m3 perfect. 1 annoying thing though M3 has a splash screen about not supported by nintendo
Ez4 i dislike since i cant load ds browser and bit slower update, its decent device
supercard lite i dont like because the file order, last time i tried it wont organize in alphabetical format or any other it just puts them in the order you threw it in the microsd hate that when i delete something and added a new item i cant get it organized