Stopping is really important especially when you spend a lot of money on your bike and wheels. I'm okay spending extra for a quality product and this is a quality product. And they work.
Works very well with Zipp break tracks in all weather. Soft compound provides no squeal, tenacious grab, and oddly I have had no imbedded debris. High price but well worth it on Daily Special.
These are to be used with carbon rims, and in dry conditions they are indistinguishable from alloy rims. Still good stopping power in the wet. Zipp wheel warranty says you must use carbon-specific brake pads and these are good ones.