I have read what is available, without buying one, on the sellers web site. It seems straight forward. What I would like to do, in addition to evaluating my boat's condition, is get an idea of the condition of a few different harbors here on Mt. Desert Island. My boat suffers zinc loss at markedly different rates depending on where it is tied up. I would like to get something that provides real information on the stray current differences from location to location. Do you think it would be possible to discern relative differences?
Yes, absolutely... The booklet that it comes with explains the process very well. You can always install a galvanic isolator on your boat if you are worried about stray current form either the marina or another boat.
Yes, I have one. I log the readings monthly, or try to. I am almost at the point of having a clear coordination between the reading and the health of my anodes. Every boat is different so it takes a while to gain that understanding. I switched from zinc to aluminum anodes and the readings changed quite a bit. No way am I going to dive the hull in this water (PNW) so I find this tool quite handy.