I've had great experience with Markel. I was routed to them through USAA and the first year my premium dropped about 40% from my Geico quote with more extensive coverage. Their annual rate adjustments are reasonable and consistent with inflation vs. the huge annual increases I had been seeing (I suspect those of us in the non-hurricane areas were being forced to subsidize those that were in the risky zone). I just checked their web site and they specifically state they insure any age boat. Good luck!