Review on High Speed Class 10 256GB Micro SD Card with Adapter for Nintendo Switch, Phone, Tablet, and PCs by Larry Morris

I bought two of these cards to store photos for use on the iPad. So far I haven't been able to copy 128 gigs to this 256G card. After about 8 gigabytes of copied data, I get an error message, after which attempts fail or take a long time. A full format in Windows alone takes more than 20 minutes. So these are very expensive cards for 8Gs. One day I thought I copied 128G but when I tried to read the data I got errors. They CANNOT be used as 256 cards UPDATE: After formatting to extFat on a Windows machine I was able to use this on a MAC machine. I still get the message that the disk/card is not recognized by the MAC address, for some reason fsck locks this card and I have to use diskutil to dismount and remount after the fsck process is complete.