This chat works like a dream in all browsers and my site members haven't reported any problems at all but have posted on the forums that they love it.
I run Buzz50 which is a site for seniors over 50 and have tried other similar one to one chats before. This is the best.
The support from the Techjoomla team is fantastic, as others have mentioned on here. Take a look at their 'About Us' page and you will see a photo of the real people who will help you :)