If you're building a community with Joomla, JomSocial is practically your only choise (CB is outdated and looks awful). It has many handy features and facebook-like UI. But, it also has bugs which the support cannot handle (search "SEF issues" / "error 500 - Controller CommunityBrowseController not found", for example). Some things which you'd think that would be simple to change or modify aren't that at all. When the support don't have answer to your problem, they simply leave it unanswered. I haven't got any help from them since I bought the product.