KO's problem has always been confidence, as the skill has been there. With him taking the opportunity to improve his strength and conditioning each Summer, I think we are beginning to see him feeling more comfortable and in control.
With that being said, I agree with Nick in that if another team looking to trade an all-star has a preference, they are welcome to their choice of the two. Sully is getting slammed lately, but I am not sure his play has deteriorated that much.