Progressive here, too. I actually just switched all my cars (personal and business, total of 5) and saved a ton. My HD truck was by far the most drastic. It was literally cut in half for the same coverage. I had no idea the variation could be so drastic. Apparently, I had tuned out all the commercials years ago :). I had previously been with Farmers.
5th wheel through Progressive was about 1/3 less than Farmers. They also have a lot of options for coverage on RVs - water intrusion, rodent damage, etc.