In Volume 1 of The Confidential Guide to Golf Courses, Tom Doak writes that.
“The Duke’s was likely the best British course of its generation, though recent efforts have certainly surpassed it. The downhill par-3 3rd and the dogleg 4th playing back out of the valley are its two memorable holes. The newer Duchess course, routed by the late Charles Lawrie and built by Donald Steel after his passing, is more heavily wooded and undulating, but more peaceful in character.”
The Duke’s course received a score of 6 out of 10 from Tom Doak while the Duchess received a 5. The Marquess Course was not reviewed.