Let's address the one difference between M3 "Perfect" and "Professional". Professional is made strictly for NDS use. By reducing the memory size, which cuts costs and is cheaper for consumers to afford, GBA functionality has been stripped away. If you're considering this product, then you're already omitting GBA playback as a deciding factor. This means that GBA ROMs won't be on your day-to-day activities, though the smaller ROMs will still work. One distressing finding was the loss of NDS-GBA Linkage. While few game pairings take a strong advantage of this, it's still a loss that may shy some users away. If GBA support isn't something you absolutely need, then this is a moot subject. You'll find everything on the NDS side to be working and pleasurable.