I can barely see the difference even after the explanation; but it's a beautiful thing to watch perfectionists creating a truly great tool, and making it free. They really are making the world a better place.
I'm only barely trained at piano - the handmade notation does look better to me, but I couldn't actually tell you why. Indeed my impression of the first close-ups was that they were pretty near identical, yet I couldn't get over the sense that one was richer, fuller. It would have been nice to have a blind study to open on - choose which of these x is the nicest rendered, state your musical training, then tell us why we like what we did.