Well, I am rating this extension excellent because it really is.
I run a website and needed a chat component that could put all users, our radio broadcasters, service providers and sponsors all in touch, real time one with another. I have tried several but run into issues of browser and other components compatibility, extremely slow response to questions (even pre-sales ones) and extremely low in features compared to the prices.
Universal AjaxChat gave me the flexibility I wanted, is full featured with security options included (eg. ban users, ban IP, etc, etc), is extremely easy to install and configured and works exactly as it advertises.
Adding to my report, I cannot commend higher the level of support I have received from the developer, both pre and after sales.
I would rate it higher if I there were more stars!
I reference to some negative comments I read here about this component, I just want to say the following "Ignorance is no reason to justify the negative expressions of your views about something that is beyond your level of understanding and knowledge".