Hi Sergio
Welcome to the forum!
Sometime back, I gave the community a challenge on my Organ thread. It was a blind test on Leslie simulations. Of the major sims available at the time, the UVI received the most votes. I gave my opinion on it. Remembering my thoughts at the time, there were very few options in making it sound like a real Leslie. It is chock full of very strange, off the wall settings. The problem is, IK Multimedia made a deal with Leslie, and created a vst with many cabinet and amp choices. There are multiple parameters you can adjust to your liking. The UVI is quite limited, but if you are satisfied with it’s single sound, it is quite good. I really prefer it on Guitar.
So is there something more you want to know? If so, feel free to ask. Below are my opinions at the time.