I've been tough on Kelly in the past, but finally on the offensive end of the court he is finding his game. The potential was alway there, not many 7' players with guard skills around. From here on, it's all about aggressive CONFIDENCE for KO. If he could just play smart, alert, defense KO will be a weapon.
Sully is a nice backup center on a contending team that will get you control of the boards, score a little, and play high IQ ball.
For me, today, I feel Kelly has the higher upside.