In addition to being lighter, higher-end Carbon blades are also stiffer. The inherent flexibility of most lower-quality blades diminishes the force in your stroke, whereas a stiffer high-quality blade transfers more of your paddling energy to the water. For the casual paddler, this means fewer strokes, less fatigue, and more time on the water. For the performance-minded paddler, it means more BOOM every time your blade digs in.
If you are on the water a lot and don’t have a carbon paddle its time to upgrade.