I've been using Joomla from the very beginning on. There are thousands of components, but many have one big problem: bad support. NOT at Core Joomla's. Maverick is the fastest and best supporter in the whole Joomla world.
I am using Commmunity Answers, Polls and Quiz on my site. The latest versions look very nice and the features are unbeatable. All 3 components are the best in their categeory. No need to look further or to be affraid spending money on. You can be sure that these components will work out of the box, do what they are described to be able to and will enhance your community with great user activity.
I am really thankful to Core Joomla realizing these components.