Ignore them! These types of outfit will simply say 'as tested by' regardless of the result....
There's no way you can win this by using science.
No matter how you 'test' it they can always say:
* It wasn't real world conditions
* The magic only happens at certain times of the day (when the grid is 'dirty')
* Your electrons might come from wind power so they're already well behaved
* Your fuse box is the wrong sort of plastic
* You wiped in the wrong direction
* ...any number of bullshit excuses
Plus: If anybody is thick enough to think it
might work they won't be swayed by reason and logic.