Pretty sweet crankset if you race cyclocross. This is my second crankset of this size, I put it on a road bike that I built for my coming tour that involves a lot of climbing. Shimano only made this teeth count combination for Ultegra, but the rest of the group is DuraAce. So far, it perform exceptionally, crisp gear switching and lightweight. The new version (R8000) is good looking too.
Maybe a tiny bit less stiff than Dura Ace . But so solid, smooths and ready to go. Snappy in acceleration and spins for days. I am sure that if you are looking to find the difference between this and dura ace you will find it . but you have to really look for it.