None of the E90s (LCI or pre) read NTFS, I have tried many times, in different cars.
All read Fat/Fat32. I use a FAT32 16gb in my car and it works fine. I see no reason why a 32gb wouldnt work. I have even heard of guys in the states plugging in 500gb HDD to the cars USB input with no errors. If you do this, just make sure the drive has good bump protection, or normal driving may impede operation.
Hope that helps.