Actually, your stats would have to be significantly lower for a CLS to be better than a whip in any situation in which you'd have to make the choice (which means every situation with the possible exception of safe PVP). If your goal is to slay or do any sort of melee training, a rapier would be much better than both a CLS and a whip, and would only get better over time. The CLS is a niche weapon with very few applications, and it's especially not worth buying at your stats.