Listen to Minotauro on this, he knows what he is speaking about. KOCII is a worthy sequel, and a better game then Red/Green. At first I was dissapointed with it because there were very few additions to the clothing part of the creation mode, and I wanted to create a variety of new MMA guys and classic wrestlers. Unfortunately, I could not. So, I was upset with it at first.
However, like Minotauro says the game just feels better. The flow of the matches is MUCH improved, there are a good deal of new moves that are pretty cool, and they fixed the little things like the camera angles and improved the speed of strikes. The result is the matches just become that much better, with moreaction and build up then Red/Green or any other wrestling game I've ever played.
Its a great game, and if you understand you won't be getting that much new visually or roster wise, but a much improved gameplay experience then you should definitely go for it. Best wrestler I've ever played.