It's really not. Not properly anyway. You'd spend a week, probably, just getting all the synchronization stuff right. Unless of course, you don't care about losing messages during a disconnection. Or you could just install this in a couple of hours and be done with it; not have to worry about security, maintaining NIH libraries, etc.
It is very easy, I have used it on various projects including chats, live dynamic dash boards, prompters and games. The SSE setup took less than a day, never had issues with sync. Never lost messages during disconnection or any issues.
I don’t know how you’ve been using SSE, but if you’ve had all these issues you must have been doing something very wrong.