FT8 supports up to 28 characters in 15 second send/receive intervals. It's necessary to keep your clock synced within 1 second of UTC. According to the documentation, FT8 is not as sensitive as the JT protocols, but is much faster.
While it's a fun, fast paced protocol, I can see it's usefulness in a grid down situation for sending abbreviated messages.
The time syncing issue has me thinking how would one accomplish syncing their computer without an internet connection?
Anyone else trying FT8 and what do you think?