My DDPai M6 plus insists on formatting my SDXC 64GB Sandisk card as FAT32. This breaks format restrictions for these cards - they are supposed to be formatted in exFAT. It won't even read on a Mac. This card is Class 10 rated @ 10MB/s and will actually do sustained transfers a little higher than that in my tests (around 12MB/s) - this should be plenty for the DDPAI with a data rate of around 10Mb/s. My Advice to anyone out there would be to stick with 32GB SDHC card, around Class 10 should give you plenty of overhead. Nothing below Class6.