Does the device [name withheld] truly “balance” the right and left brain hemispheres as advertised, and what, if anything, are the benefits?

This balances the hemispheres with respect to electrical activity in the moment. That is not the same thing as having a deep resolution of inner conflicts and issues and the deep karmic roots inherent in destabilization of a person through many distorted patterns of conduct, behavior, and memory influences. So it is a temporary manipulation of neural functioning that may have a perceived beneficial change in mood for some and a stabilization of emotions may well happen. But that is more through an interruption of what may have been rumbling prior to the treatment than it is a representation of a permanent change for the better. That will not happen as a result of a manipulation of the current energy within the body in this way. It is much like the many energy healing modalities that impinge one’s own energy or that of the Divine through the healer’s hands in shifting energy among the planes of the body and the meridian system to resolve some blockages and bring things more into balance with respect to the chakra functioning in particular. While this has short-term benefits, it is not deep healing and therefore, quite limited in value.