It does not slow to fill the card, I copied it to 27 GB and test all between 25 and 30 minutes, and is formatted in FAT32 factory.
I tried maps! Classes 10 that went down to less than 6 MB / s on the same small files, amazing right? :)
Small staff BĂ©mol, this card I ordered it for my neighbor LOL but I think soon buy a 64GB the same style to replace my current 32 from another brand.
For me this card is 10/10 :)