Although the film was a pleasant diversion, not once did I feel I was watching Grace Kelly. As a few other reviewers also noted, the attractive Cheryl Ladd neither looked nor sounded like the actress turned Princess.
And, although a fan of his, an also miscast Ian McShane came off as a rather smarmy, smooth-talking Prince Ranier. As I recall Ranier's appearance, the actor who portrayed Clark Gable (in the film's brief scenes from the movie Mogambo) looked more like the Prince in later years.
On the other hand, Lloyd Bridges and Diane Ladd were very credible as Grace's parents, the robust and athletic Jack and the refined and tactfully outspoken Margaret.
Additionally, the actors portraying Edith Head and the aforementioned Clark Gable gave convincing lookalike performances.
Overall, as Hollywood "bio-pics" go, this was an average yet mildly entertaining film for Grace Kelly admirers. Personally, she was never a favorite of mine and I thought her voice was annoyingly affected.
As a final note, the film's end credits stated that it was made with Princess Grace's approval. Go figure.