Originally Posted by El Chaba

I have two bikes equipped with Delta brakes. The first has the “version two” or the first un-recalled version. These are finicky to set up and have admittedly less “ power” than a modern dual pivot or some other brakes. They have fantastic modulation, and I have never experienced any of the non linear response issues that are sometimes reported. These were my all time favorite brakes for subtle speed adjustments in a tight, crowded pack in a criterium or road race.
The second has the final version. These have much more “power”. They require more effort than the dual pivot model that replaced them, but the power is adequate to max them out without undue hand effort. For this reason, I preferred this model for hillier rides and races. Modulation is good, but not as good as the previous version detailed above.
As another note on Deltas….If you have a set that you are using, CHANGE THE PADS. For some reason the Delta pad material seems very prone to hardening. Get a set of the new Koolstop pads or a properly stored set of originals. The fresh, uncompromised pads are essential to the performance of these brakes.