Item rating is definitively the most powerful review and rating system for Joomla and Jomsocial.
The extension has the voting flexibility you've ever had before. You can add unlimited group with some criteria set inside. Each criteria can be a different voting tool like percent bar, star, icons or thumb up/down. If you're a webdesigner, you'll also like the custom design tool in rating group with element positions definition.
Works with Jomsocial profile and Jomsocial group
Item rating got also a powerful voting restriction: you can allow vote only from backend, from frontend, from both, allow only certain Joomla user group. All the possibility are covered, only voting from backend, only from frontend or match both scores. We were just saving the best for last, it works with rich snippet review microdata (to make appear star in search results.