How's Multiplayer Perfomance nowadays?

I've clocked in 100 hours before the cartel update and i'm looking into starting a new run.

Back then coop had several issues with saves, desync and game breaking bugs, like the NPCs and quests failing to register flags for clients (while hosts were fine).

So here i am asking if those issues have been fixed in order to decide whether to start singleplayer or to pull in my buddies for some coop sessions.