I'm seeing some less than optimal partitioning for several processor counts using both Metis and Hilbert SFC.  Also from what I can tell, Morton SFC is completely broken.  I realize that I'm splitting a small mesh among a lot of processors, but the behavior is still pretty bad.

The following pictures are using mesh generation (16x16), no refinement:
https://drive.google.com/folderview?id=0B8csupg5nQaady14UFZjVUMzSm8&usp=sharing