Are using the regular stock emulator or CatSFC? CatSFC seems to work a lot better. Either way, it's still leaps and bound above SNES on a normal flashcard. Not perfect like on a Wii, but you can only expect so much.
That's not true. The dstwo has enough power. All what it takes is proper codingYou'll have to wait for 3ds mode homebrew if you want perfect snes.