This is true, but I find that I am using my DS and my GBA/SP hardly at all anymore, now that I have my Dingoo!!
I only use them, basically, when the battery is dead in my Dingoo!!
Or, if I want to play an NDS game, since Dingoo won't emulate NDS.
I doubt dingoo ever will be able to emulate NDS, incidentally, since NDS has 2 screens, and Dingoo has but one.