I really don't think there is much you could do to break your DS with this thing. It is just like a game cart with a MicroSD card slot. There are other forms of DS modding that could do damage, but this R4 thing is pretty safe. I remember back in the N64 days everyone was saying that if you use 3rd party controllers or memory cards they might break your N64. My friend even told me that my warranty would be void if I used a third party controller. Six months after buying my third party controller the joy stick went out on it, proving that there was a ligitimate reason for not buying 3rd party, but it wasn't because it would break my system. Maybe Nintendo employees go online and spread these rumors in order to keep people from buying things like this.