I’m afraid I can’t tell you which one you should choose. 🤷🏻♀️
Every plugin has its limitations and advantages. However, I’m sure you can understand that it’s hard for the authors of a plugin or even a theme to spend free time to answer users of their free plugin.
The fact that Youzify is paid already ensures that the authors will be able to give you more time to answer your questions and solve possible issues. We found this website where severals plugins are described: 10 Best BuddyPress Plugins for Adding Cool Features.
It seems Rt Media and Youzify are listed on this page. We think it might help you learn more about these plugins to make your choice easier.
Hope this will help you.