I had a friend with the Skakti stones. He also had the little tiny bowls that would hit right at the spot of the reflection point. He had a beautiful Luxman Magico system.
I think if any of these chockskies did anything at all, it was to help him pay attention to everything. It all matters a little and if that stone brings you deeper in to paying attention to other areas go for it. You can even pay $4000 for a rod with resonators on it. I saw an $18000 power strip the other day.
Sometimes the ritual of using something deepens our appreciation of the hobby to the point that makes it worth it. I haven't used the Shakti stone but a few of the other above with some outcomes harder to hear than others. Go after the speaker positioning so it grips your room, locks in. That's worth about a $10,000 improvement if you get it right, and it's free. Get the stone too.