With claws you have 4 attacks, sure - You can hit over 1,000. But you can also miss the special entirely, wasting 50% special. With Korasi's, you can use the special, 60% of the bar, and pretty much get a guaranteed 450 average. It has a much higher potential to have a critical hit over D Claws, and is great one you get a target to 50-60% health.