NTFS is now transactional. https://en.wikipedia.org/wiki/Transactional_NTFS
exFAT doesn't have that so a little more speed. https://en.wikipedia.org/wiki/ExFAT
You want safe or speed?
I just got a brand new 64Bit USB 3.0 flashdrive and its in an exFAT file system format but I want an NTFS format because I've never had issues with them before and the max drive name length is insanely small on the other formats, I use windows 10 and the allocation unit size is 128 kilobytes which I like, Will I see a very noticeable speed decrease if I do this?

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