Just do a little research on HFS+ issues. It is not a small problem. This was one of the reasons why the OS X server was killed.

Some limitations that really do have a major impact on people: (Features Missing)

    data checksums


    nanosecond timestamps


    concurrent access (let more than one process at the time access the filesystem)


    checksumming


    snapshotting


    longer time frame (February 6 2040 for HFS+)


    sparse file support


    real hard links