I have heard the opposite. aluminum boats have bigger problems than fiberglass. I will not fish for kings without the BB. The very first day I had it in the boat, I decided to wire it into the battery while trolling for blackmouth with my brother. He was driving the boat while watching the downriggers, while I was under the console running wires. After an hour of fishing we hadn't had a hit. When I finished I turned it on and it said my "natural current" was .89.... .6-.65 is ideal for salmon. I switched to applied current (where you control it) and dialed it to .65 my hand wasn't 2 inches away when my rod buckled and I boated about a 9 lb blackie. A few minutes later my brother had his and we were done. I know this could have been coincidence, but it happened several times this summer too. (nevermind the several times I'd unplug someone just for fun...) Once, I forgot to hook it up while trolling at Umatilla Reef, fished for nearly 45 minutes before I noticed. I hooked it up and dialed it in.... 28lb fish the net within 15 minutes. There are plenty of other examples I could give. Too many for it to not work in my opinion. If you boat's natural current is close to .65 you wont notice much of a difference. If its way hot like mine, it'll make all the difference. Incidentally, my brother bought a new hewescraft searunner like mine and had the same problem trolling at Pt. Defiance... few hookups. After seeing it work in my boat, he bought one, caught more fish... you decide for yourself.