It's kind of perplexing, because Ken Cassens, describing flying the Old Rhinebeck "Spirit" reproduction, has said it flies well. However, you have to realize that he has had a lifetime of experience flying aircraft of that era and earlier. (Internally, the aircraft doesn't have all of the fuel tanks the original did, and only flies with enough fuel for a regular flight time, and carries ballast in the nose to make up for the loss of weight). For those who have flown some of the other reproductions/replicas, like the EAA example (which the FS2004 "Spirit" flight dynamics were modeled off of), they describe it as behaving very much like the FS2004 model behaves. In an interview in the "One Six Right" documentary, there is an old pilot who recounts how he made a flying model of the "Spirit" as a child, and it flew awful - later, when he had the opportunity to meet Lindbergh, he told Lindbergh about the model and how terrible it flew, and Lindbergh commented that it must have been an accurate model as the real thing flew the same.