The support is second to none and the only problem I had was not caused by the extension but my Joomla setup - fixed by the author within a couple of hours and now working perfectly. Just remember if you want support with the Pro version, let him know the version of Shoutbox and Joomla that you're using and do read the instruction for installation. For what it is, this extension get full marks and I recommend it!
My only tiny caveat is that it isn't immediately obvious how it all works together and I would have given up if I didn't "feel" that it was a winner. Setting up the form is easy enough and there's lots of flexibility. However, I got a bit stuck when it came to the last bit, namely Submit Actions. Senior moment perhaps but I didn't realise (and nowhere in the FAQs does it mention) that you can set up any or all the available functions. Indeed you must! The trick is to make sure that the last one in the list is Redirect and you'll find it works like a dream. Just don't give up if you don't quite get the concept at first - it really does work superbly!
Thanks for your feedback. Its important I think to point out that users DONT have to use the "redirect plugin" after the submission if they dont want to, you can simply add the "HTML (Thankyou)" plugin and display a thankyou message (or other HMTL Text) on the landing page :-) :-)