Ron Guth:
The 1907-S Half Dollar may be a sleeper no longer, but it is certainly a rare enough coin. It has one of the lowest total populations of the later-year Barber Half Dollars and it is sufficiently scarce in Mint State that it deserves respect from collectors. It compares favorably with the 1908-S, which is another tougher date, and it is even more challenging in Mint State than the venerable 1906-S. MS66 examples are very rare, with only a couple of MS67's besting them. The finest example of which we are aware is the colorful PCGS MS67+ that once graced the collections of Dr. Duckor (and his wife) and the late Eugene Gardner.