I'm usually hesitant when it comes to commercial software because it's a financial investment, but JomComment was more than worth its reasonable price tag.

After testing numerous comment systems for Joomla!, none of which reached my expectations, I took a gamble on JomComment and boy did it pay off! Its various themes are all attractive and functional, and the slick AJAX adds a touch of class and professionalism. The back-end is equally attractive and functional, with more options than you can shake a stick at: everything from spam-protection to bbcode to - very importantly - perfect Community Builder integration

The component is so easy to install and use that you won't need to ask for help often, but the few times I've had to e-mail their support staff, the responses have been quick (no longer than 1 business day), friendly and genuinely helpful.

I really can't sing its praises higher than that. Now that the new version 1.8 has been released and the few minor complaints some users had have been addressed, I can't think of a reason - short of complete poverty - not to buy this component. Practically essential.