These polymer coated brake cables are very slick. The installation was very easy, and am using them with the non 9000 or 6800 series brakes, (7900). I did take care though to scrape off the cable coating where it gets clamped in by the fixing bolt, I'm a bit paranoid about the cable slipping through the clamp. Great cable.
I bought this cable set for a bike equipped with Ultegra 6500 (Shimano does not approve the use of these cables without Dura-Ace 9000 brakes). The polymer coating on this set can be scratched off with sandpaper, so that is what I did when securing the cables in the brakes. Great set of cables, probably the best you can buy.