Ultrasonic Antifouling Experience

Has anyone used this?

I have a friend who wants to use it so that the boat can stay afloat pretty much permanently.

Thanks!

Tony, These guys were selling this at Southampton Boat show last year, I have not used it.
http://blueandgreenmarine.com/how-it-works.html

Coppercoat is proven to work. Ok you end up with a brown antifoul but its below the water anyway.
My Dad has it on his Aquabell and when lifted out it did even need pressure washing, it was spotless, no weed slime or anything like that.