I have used 123 Flash Chat three years, this software really makes my site popular. They add many new functions into the chat. Now they released 10.0 version, the HTML 5 client is very good, loading fast. You can test it here.
And i can also earn money with 123 Flash Chat, you can check the method here.
Thanks, if you also want add a chat into your site, 123 Flash Chat will good for you.