I had the KG-1, now discontinued. I chose it over the more expensive models with speed control, because if you need to run the media 24 hours, why would you want to slow it down more?
The media didn’t impress me. Dried garbanzo beans, rice, seeds, with diamond dust, some steel shot for weight. On my first try it left sharp zig-zag scratches in the one piece of silver I tried it on. I examined every single steel shot one at a time, could not find the cause of the scratches. On day-long runs after that it didn’t seem to do much. Other than the scratches you could chalk it up to my expecting too much or not prepping the pieces well enough, I don’t know.
More recently, after a long stretch of non-use I replaced the seed mix with small ceramic media and liked the results. Then the motor died.
Since the machine basically moves the media in a circular path, a small rotary or vibratory tumbler makes as much sense. Perhaps their media has value.
Again, you could blame it on the user (me) and I wouldn’t argue strenuously, but that’s my experience. I much prefer fast-rotating barrel tumblers.
With a little effort you could buy a barrel to your liking, get a motor (Fasco makes good ones with circuit breakers for overheating protection) a pully or two, rubber belt, steel rods, and you are good to go, saving a lot of money.
My 2 cents.