I have been using their platform for almost 2 years now to run my community of young professionals (18-35) in Canada called "Inner Circle".
It is free but requires you pay out an amount monthly that varies depending where are from within North America or Europe etc so it's not super cheap compared with other platforms like Facebook Groups/Twitter lists which offer more features at no cost! The main benefit we've seen since starting Inner circle has definitely helped our brand grow; however many people who aren't already engaged may feel intimidated by this approach as they would prefer something less formal - just be prepared when launching new members into group activities such as games & challenges if necessary otherwise some can get rather bored very quickly especially those outside US timezones e.g Australia + 1hrs ahead). We use all aspects provided including private message system between groups plus activity feed similar to.