HYPERs, on the other hand, are faster, especially on flats and in rolling terrain. They maintain their momentum better. They also feel stiffer, so they are not too comfy on harsher roads. They feel slightly less responsive and have worse crosswind stability. I also wrote an in-depth comparison on my website if you are interested.
Yes. I've tested around 10 wheelsets (all with the same tires and tire pressure), and carbon-spoked ones are usually stiffer and less comfortable on harsh roads than steel-spoked wheels.