ZDitto
Best Multistreaming system, with lots of bonuses.
I honestly don't know if there is another, better multistreaming program, but I will never have to look for one now. I use Restream to simultaneously stream to both YouTube and Twitch at 1080p 60fps. I just connected my accounts, plug in the stream event, and start streaming from OBS. I have never had issues with them, and the few times that I had questions, they were quick, helpful, and above all, actual people. I also use their Restream Chat application to have both my Youtube and Twitch chat in one place (also has an "always on top" and transparency feature.) its the best. Seriously. These guys are awesome. I even get custom reports after every stream sent to my email within minutes of finishing. Best part: it's 100% free for what I am using it for.



