Utsuho Reiuji said:
Normally I'd side with the AK2i....
However this time I'd suggest the Supercard DSTwo.
Built GBA Emulation, soon to be SNES Emulation, and one of the Best Guis I've seen in awhile.
The Supercard team also seems to have the longest running support coverage of any cart developer. Heck, they still support their slot 2 flashcarts.
This^^
At first you'll be happy with what the AK2i, but if you get the DSTWO you can get so much more, and even more coming, with great support.
Just like how you want more than your R4, I'd suggest the DSTWO just so you don't have to upgrade again if you want all the extra stuff later on.