Open Stack

Please ask this question on openstack-ops, where a lot of operators
convene and can probably share experiences with the SDN controllers you
listed. 

My gut says that an SDN controller is expected to handle multiple regions and large
topologies, but I can't comment on if any SDN solution handles this
case, with any authority. I would imagine so - but you'd have better
luck on the ops list for specific controllers

-- 
Sean M. Collins