I used botox for a few years. Initially the results were miraculous, with pain relief starting after about 4 or 5 days. I would highly recommend it IF you can find someone familiar with both injecting the face and with botox. There is the chance of drooping and weakness with botox, so you really do not want someone using you as their first experiment.
I have only heard of a few other people who have tried it, but all have had some degree of pain relief. I finally had to have surgery since meds and botox were not providing enough relief. Otherwise I would have continued getting botox injections. Hope this helps!