I’ve used OBS on Mac for Facebook Live. I like it a lot. One particularly cool feature is being able to set up several “screens” and configure keyboard shortcuts to jump between them. So for instance, if you have several webcams set up,
you can switch between them easily. You can also use the entire screen of your computer as an input, as well as the individual windows of programs. OBS will also record and stream at the same time, so you can go back and slice up your video for later use.
I haven’t yet figured out how to stream to multiple services at the same time with OBS, or how to change the resolution of the streamed video.