A rate that fluctuates between 6 MB / s and 12 MB / s max great for large files (8 GB). In short it is very slow.
I said that I tested NTFS and EXT4 on 2 different PCs and NAS.
I bought this key curiosity by seeing its popularity on Amazon and the number of comments, I was missing a 32GB.
If you want a quick key, do not make the same mistake as me, it is really part of the less rapid key.