I use BOATUS, and have been since 1997. It's around $300 a year for a new H16.

I can't speak to their service level personally, as all I've ever needed them for is to take my money (actually, that's a good problem to have).

At the time I started using them, my insurance agent recommended using them (and he didn't represent them). I was also told by other sailors that they were the only company that would insure you for racing. I think US SAILING got into it since then.

Mike