Aeon is the big Motor home insurer, or was,, But that said many other companies do decent RV policies,, I'm not a fan of Flo, for mostly "Fed up with the ads" reasons.. Can not actually say anything about Progressive, it's Flo I don't like.
NATIONWIDE insures this motor home at the moment, They have done a decent job of it up to the point where wife and I bought a used JEEP.. Under both MI and SC (where we bought the jeep) law if you have an existing auto policy coverage is extended to a new purchase for a short period of time (Not sure now long but it is at least a week) to give you time to get to your agent... Well. I tried but agent did not return either E-Mail or phone call and he retired effective the day Wife totaled the car (4 days, 2 business 2 non-business after we bought it) ... Nationwide claims I made no attempt to contact and that the RV is not an automobile and refused to sign the Financial Responsibility form.
That's why Im' shopping for a new company. E-Surance covers my car.