has anyone tried Botox injections for migraines?

I have been seeing a neurologist who specializes in headaches for going on 3 years now. We have tried more med combinations that I even care to remember. None of which had much benefit. Curently I am on propranolol, prozac,zanaflex and zomig. I continue to have daily mild to moderate headaches and migraines 5-7 times per month. I have also tried relaxtion therapy, massage therapy and facet injections...no help...although the massage felt wonderful. My Doc tells me we are out of med options and wants to try Botox injections. They are not FDA approved for migraine treatments (but have shown promise). Since they are not approved insurance will not pay for them and they are expensive. I am willing to try anything but money is tight since I am unable to work at this time. Has anyone ever tried Botox injections for migs and if so did they help?

Thanks,

Anita