I've played with implementing both SSE and websockets on embedded hardware, and SSE is nice because of the simplicity--no need to do a handshake or other setup

I've played with implementing both SSE and websockets on embedded hardware, and SSE is nice because of the simplicity--no need to do a handshake or other setup like with websockets. If you're primarily sending data from the server to the browser, SSE + a simple REST api (to send data back from browser to server) is a pretty nice combo.