OREANDA-NEWS. A.M. Best has upgraded the Financial Strength Rating (FSR) to A++ (Superior) from A- (Excellent) and the Long-Term Issuer Credit Ratings (Long-Term ICR) to aa+ from a- of Mount Vernon Specialty Insurance Company and Radnor Specialty Insurance Company (both domiciled in Omaha, NE), strategic affiliates of United States Liability Insurance Company (USLI) (Wayne, PA) that are branded as Devon Park Specialty. Concurrently, A.M. Best has affirmed the FSR of A++ (Superior) and the Long-Term ICRs of “aa+” of USLI and its subsidiaries: Mount Vernon Fire Insurance Company (MVF) (Wayne, PA) and U.S. Underwriters Insurance Company (USU) (Bismarck, ND). The outlook of these Credit Ratings (ratings) is stable.