As a former antique dealer, collector and R9 owner I can tell you that the value of the Rohrbaugh is assured, particularly those who have low serial numbers.
Ironically, value is sometimes established by product failure or rejection at the market place. Case in point: Model 65 Winchester. This was a half magazine "improvement" over the mighty Model 92. It failed and they made only several thousand of them. Check out the value of a Winchester Model 65 today.
Another thing that will diminish values of contemporary guns, in the future, is the disappearance of cardboard boxes. New guns come in plastic lockable containers; a dime a dozen, whereas old guns came in boxes which, if preserved, greatly enhance the value of the pistol. (Happily, I own 6 old Colts in original boxes).
MountainMan: I am an Honorary Member of the Knifemakers Guild and I must tell you that you have great taste if you carry a Tony Bose knife.