Do you set bandwidth limits for each user?
I've been slowly making the transition from Plex over the last year, and I'm at the point where I'm ready to tell my small handful of users to download the Emby app and switch over.
One thing I've noticed in Emby is if a user attempts to play a file which is higher bitrate than their connection allows, the app just kicks them back to the menu without any information about what went wrong. The solution is to adjust the maximum quality setting downward until the bitrate fits within their bandwidth. I ran into this getting my girlfriend's Roku set up on our home network.
Now I'm curious - do you set a maximum streaming quality per user based on what you know about their connection quality? I have a number of high bitrate files I'd like people to be able to watch (either direct stream, or more likely transcoded) but I'm used to Plex handling the streaming quality to match the connection, and Emby doesn't seem to do that.