I own an electric drumkit and wanted to make it completely silent by reducing the thumping noise of the kickpedal and hi-hat controller. At first I did not want to buy the noise eaters because of their high price. But I quickly found out that there were no other alternatives. Eventually after some hard thinking, I decided to buy the noise eaters.
When they were delivered to my house, they were surprisingly heavy and bigger than I expected. I could tell this was a quality product, but it still did not live up to the high price. After some testing I can confirm that the noise eaters were able to dampen the thump heard downstairs. Roland claims to reduce the noise by 75%, but in my experience it was not this big of a change. I would say it will help reduce the thump up to 50%. The noise eaters do not wobble as much as I imagined. The kickpedal and the hi-hat controller remained relatively stable.
Because of the high price of 100 EUR per piece, I do not think I would recommend this solution. The price is not worth it for what it does (or claims to do).