There have been a lot of different methods to transfer save files from a DS and 3DS Game Card, but none of them have had as much support and functionality as the R4i Save Dongle.
The R4i Save Dongle is made by the same people that made the R4i-SDHC (Also known as R4i 3DS), in my experience they are very reliable and won't rip you off or give you any "clone card" garbage.
At first the transfer program had some annoying graphical bugs, but that was quickly fixed by them in an update.
Transferring save files is quick and easy, with choice of file name and destination folder.
+ Quick and easy way of transferring save files
+ Lots of support and functionality
+ Dedicated community for sharing save files.
- Design makes it a bit awkward to fit in another USB to the port(s) next to the Save Dongle
Overall, the R4i Save Dongle is the best choice for transferring DS and 3DS save files.
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For those of you who are wondering on the quality of the save file and want to check for themselves, I have uploaded my Mario Kart DS save file that I copied during the review.
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