I had BoatUS for the first couple of years on 'Anomaly'. Premium was $8000 in the Great Lakes, when I told them I was going to Newfoundland they wanted to add another $2400 rider. At that point I began shopping and ended up with Susan Ratrie at IMIS. She has been great, is a cruiser herself, came up with quotes from several companies to compare. I finally went with Seaworthy LLC (through IMIS), this is the same company that underwrites most BoatUS policies, coverage is the same or maybe better, $4300 or so including the Newfoundland rider. In other words less than half price for the same coverage from the same underwriter. I have no claims history with Seaworthy (and no claims history at all with any boat), but they are a Berkshire Hathaway company so seems like they have some financial resources.
So it pays to shop, and I would heartily recommend contacting Susan: