The SD is some cheap 64GB no brand, heard a number of people have had issues so will be moving to a decent branded one soon.Interesting device. Can you install Windows on it? Thinking PCem then setup a DOS and maybe early Win95 environement.
Edit, it seems not but it does look like there is already custom firmware 'GarlicOS' and can get other system like the Amiga working to some degree.
I've ordered one direct from ANBERNIC though, which came to £69.85 GBP inc delivery. Even if I play a few games and don't use it much, they seem popular on eBay for futur resale.
What type of SD card does it take? Are both slots MicroSD, what is TF 'Dual card slots, support TF card expansion,'
You can have everything on a single SD card or split the OS and 'data' between two.