An independent test for this is real easy. Just get a 15' cat without paint. Now put one transducer in one of the pontoons and not in the other. Now put it in the water for a month or two depending on where you are and then have a look. Leave the antifouling paint out of the equation. Yeah its says you need it, but if it works, it should inhibit growth in a noticeable way on gel coat between one pontoon and the other over x time. If not, its not working. If so, I'd buy it.
This is such a simple test study. I don't see it having been done anywhere so far (publicly anyways). If I owned the company, the first thing I would have done is run that test, and I'd have photos all over the internet showing/documenting the results if it worked well. I see no real world tests - nothing..
The reality that there's no simple test studies like this readily available on their site after 10+ years tells me a whole lot.
Show us the money!