I did use a Sandisk 32GB Class 10 SD card in it for a while, but it was mostly for music and the like. Now that I'm using an Android for that kind of media, I decided to swap back to the 2GB SD that came with it. I prefer physical media, so the SD card only contains updates for my cartridge games and some random small eShop games like Shovel Knight. The 2GB SD is formatted to FAT16 and performs quite a bit better on the load times (for example: when you first turn on the 3DS or when you start up a game stored on the Micro SD).
