I have been using a broker for the past 5 years for my homeowners and auto insurance, even though I've been with the same insurance company, Pemco, for over 30 years.
Surprising, going through the broker instead of directly through the company was cheaper and every year, I compare Geico, State Farm, Progressive and others, they still have not been able to beat the price of my present insurance provider. Pemco started out in Washington state, then a few years ago, they have gotten into selling insurance in Oregon and California.
They are a tough company to get if one has had numerous claims and traffic tickets, but their service is awesome.
I also use the broker/Pemco for my classic car insurance, which is with Haggerty. Haggerty is also a broker, again great service and prices.
I would check with a broker, then go online and search for the reviews from customers on the various insrance companies the broker selects. Others in this thread have also provided some very good information on insurance.