As promised, I am now posting some comparison pics for interested parties.
Some of you may know that I came across a cased Darwin at an antique store about a month or so ago. I was very excited to find a Darwin in the wild. Imagine my surprise when I got home to find that there was no possible way to put a blade into the razor. This led to my asking Connie and others about my apparently unique or at least very rare Darwin. There seemed to be some interest, so when Connie's Darwin got to my house (on the Darwin pass-around), I took the opportunity to take some photos of them side by side.
Mine is on the left in the first photo, and on the right in the second two photos. Notice the differences in the top cap and in the baseplate. Connie's has bullets like an Old Type, whereas the bottom of my Darwin is completely flat.