In my experience, Emby is a litter better, as it doesn't force transcoding as often. The interface isn't that nice, though.
For example, I have a 4k 10 bit HEVC file that I want to play on my Fire TV 2. Plex forces a transcode (which sucks transcoding HDR), but emby direct plays it.
I would hold out and wait on Jellyfin, if I were you. Open source and free fork of Emby that is getting started.