I found this a pretty interesting extension for Joomla, but there are a few things that I would like to point out. When I installed on my regular site it went to a blank page, when I installed it on a test site. It worked on my test site. I figured that I had something on my test site that I didn't have on my normal site. Then I read that it 'works with' community builder. I had that on my test site, but not my regular site. So it doesn't work with out Community Builder. Next when I first created a group, It said that some MySql Queries where missing, but once I edit the group that disappered. Other than those few minor flaws this works great for me. Nice!