I don't know how they would be with a claim. I also don't know how my local broker's insurance would handle a claim as I have not had one in 45+ years operating boats. Insurance is just one of the necessary evils in this world.
When I purchased my boat in the States it was at the bottom of the US recession and the broker (one of the few in my area that does boats and the only one that I had dealt with before) would only insure the boat for the purchase price and not for the actual value here. I got a really good deal and the boat was instantly worth more here than the amount I paid for it. The only way they would raise the value was for me to have a survey done which would have cost me a fortune since I live in the Kootenays and the closest surveyor was in Kelowna. I was always unhappy with the idea that I could only insure the boat for approximately 70% of it's actual resale value.
When I filled out the Portside questionnaire I put in the actual resale value for the boat that I came up with from looking at ads on Craigslist and Kijiji. Portside quoted on this value with no other requirements. No problem. I got the boat insured for the real value of the boat and many better clauses for a MUCH cheaper rate. The only thing i found lacking from my previous policy was the "Lay Up Period December 15th to March 1st". This did not bother me and if you use your boat in the winter they will allow this for a premium. This company was much easier to deal with than my local broker. They know boats. The local broker, not so much. Boats are not what they specialize in.
I hope this helps.
Jack