Chris,
The subjects of occipital nerve stimulators came up at the November American Headache Society symposium. The concensus of the doctors there was that they're "not ready for prime time." I don't look for FDA approval any time soon. There's an issue with the leads slipping out of place, which renders the stimulator useless. Most insurance compaines do NOT cover them for the treatment of Migraine. There's more information on this in Occipital Nerve Stimulation for Migraine and Headache Prevention - 2008 Update.
Most doctors follow the "gold standard" of the International Headache Society's International Classification of Headache Disorders, 2nd Edition (ICHD-II), for diagnosing Migraines and other headache disorders. "Complex Migraine" is not a standard diagnosis per the ICHD-II, and when it is used by doctors, it's used differently by different doctors. That makes it hard for me to know what kind of information to offer you about your Migraines.
You may find that Namenda helps with your Migraines too. Some have found it effective as a Migraine preventive. For more information on this, please see Namenda for Migraine and Chronic Headache Prevention.
I hope this helps,
Teri