40 years ago I would have been VERY interested! And the price seems reasonable for what you get.
...In the real world, I don't think a balanced phono connection really helps with anything. A phono cartridge is "balanced" and I don't think grounding one side of the coil connections hurts anything (you shouldn't get ground loops there). And a balanced connection won't eliminate hum pick-up by the coil.
The balanced outputs could help with some nose & ground loop problems with that connection.