Really depends on how badly you want to play those GBA games and if you're interested in any of the other DSTWO accelerated plugins. It's the best option at the moment and an excellent card, but if you can't see yourself using the features then you may as well stick with your existing cart. On the other hand DS2x86 is maturing rapidly and opening a massive library of old DOS games at decent speeds, there's the new Atari 7800 emu, SNES of course, I can't imagine it'll be much longer before a quality Genesis/Megadrive emu is done (but maybe I'm too optimistic). There's a lot to play with and if you're likely to use more than just the DS features it'd still be worth every cent at twice the price.