I have a new 128GB Extreme Pro that I use to exchange files between OS X and Windows, so while FAT32 will work, it is an older file system that has some limitations.
exFAT is available on both OSX and Windows machines and was designed and optimised for flash storage, so I’m thinking of reformatting my drive to be exFAT.
Currently, it looks promising. I’ve formatted the Extreme Pro with exFAT, encrypted the drive using TrueCrtpt, formatted the encrypted volume using exFAT and I’m now copying files across to the ecnrypted volume.