I use a Roland MV 8000. It has USB transfer (1.0 sadly), it prefers aiffs, & uses an FAT file structure. My op1 transfers aiffs over USB as well, & I believe also uses FAT file structure? Dare I think they could be friends? I.e. shuttle aiffs back and forth, with an adapter maybe?
You would need to use a computer or another USB host as a gobetween I believe.