WTF are you talking about? Yes no$GBA plays many DS games, and it's usually just as fast if not faster than the other DS emulators. You just have to go into the options and change the save type/size for each game before resetting the emulator. DS emulators for the PC are still early in development. If you think it's "crap" then please write your own emulator and prove that you can do better.
And I have no clue what you're talking about when you say a GBA emulator for the DS, as nothing of the sort exists as far as I know.