I had my Speedster insured with Liberty Mutual for 18 years, but as a '69 VW convertible, agreed coverage of $25K. As soon as I re-registered it as a '57 Porsche Replica (based on a '69 VW) the local office freaked out and wouldn't touch it.
Went with Hagerty, instead, for less money than LM, slightly better coverage and >5K miles per year. Their on-line support is very good and I never have to see the local office.