Toy, agreed. Practical versus cost (in media and related equipment), not sure.
You can run your vibrating tumbler and bags of cob or shells for what it costs up front.
Not a must have here but I use spehical stainless instead. You can use those in a vibrator as well.
Just happened to have a bunch from a job left over.
I tend to load the tumbler and let it go in the shop for at least 8 hours (with cob/shells). I'm not in a production scenario so time isn't an issue.
IMO, it's a gimmick. Practical, maybe, up front cost, excessive. I can put that money toward something else.