I have two restored Doodle Bugs insured with Hagerty. I've been with them for, I think, 4 years now. I've never had to file a claim, but am happy with their service and their prices seem competitive. The biggest thing for me is that Hagerty "gets it" when it comes to scooters and motorbikes, and antique/vintage vehicles. I know that if something happens and I do need to file a claim that I am dealing with the right sort of company.
In my case I have them insured more to protect against the risk of theft and fire (and because proof of insurance is required at some sorts of shows and almost all museums).
Although Doodle Bugs were ridden on the street in the 1940s, there is not a chance they'd be street legal today and I wouldn't feel safe riding one in traffic even if I fought to get it grandfathered in. So...mine are not registered or plated and not operated on public roadways. Because they are insured but not registered, each year the State of Texas sends me a letter asking me why I have insurance on two unregistered vehicles in my name and at an address in Texas. I send them back the same reply each year and they've never seemed to have an issue...until the following year when I get the exact same letter again.
That ultra cheap storage insurance through State Farm does sound interesting and in incredibly cheap. How do they define "storage" and is that for an agreed value policy (as opposed to stated value or traditional) as Hagerty is?