Correction on the saddle size calculator: Thigh circumference, not length. Somewhere on Angelfire. Somebody posted a different chart that goes by length. My mistake. I can't find the link to the Angelfire page. It's on my dead computer.
Right about 16" is mostly a child's size. It's also a lot harder to resell at a good price than a 16.5 would be. 17" is the average size for a close contact saddle.