RTMS-Has anyone had success?

My son, who has schizophrenia, has had increasing auditory hallucinations, a voice taunts him and hits his head repeatedly. He only recently told me about this torment even though he has been dealing with the illness for ten years. He takes his medication, clozapine, ingrezza and depakote, but more side effects are appearing. It seems there is no end to the addition of medication and he is only 26. I want to encourage him to try the repetitive trans cranial magnetic stimulation. Has anyone had success with it for reducing or eliminating voices?