Rolex USA sent me the 116613 for evaluation so I've been playing with it this weekend.

My initial reaction is that as much as I like the bracelet upgrades, I'm not big on the thicker lugs. The older 16613 just seems more elegant to me, particularly how the bracelet more proportionately tapers from the case.

Getting an accurate shot which shows the difference in the color of the dial/bezel of these two watches was difficult, but this shot does the trick. The 16613 is a bit darker blue, and the 116613 has a uniform, consistent blue color.