I just picked this one up and have to say that on a scale of 1-10, not counting the replaced band this one is a 9.999. Watch is in literally perfect condition with no wear, marks or scratches whatsoever. No case wear on lugs, sterling bezel ring, around the crown or on high points of case back. Movement is like a mirror. Case and movement both dated L1.
If someone handed me this watch in a box with a string tag and black suede band on it, telling me it was NOS, I would have believed them. The only give-away would be the single jeweler's mark on the inside case back.
1951 Air King - the nicest one I have ever encountered