Played in open since launch, mainly trading, spent most of the time in high human pop areas. Not a single bad experience. I actually think most of the bad experiences you hear online are absolute complete overreaction, or complete nonsense, one bad experience in countless hours and they are complaining how the game is full of griefers, the funniest are the ones complaining of griefers who try to pirate them, and logging off to stop them, irony at max. Infact out of every single griefer complaint thread I have read I dont think a single one was legitimate.
Most of the experiences you have will be friendly, alot will ignore you, some will chat, most are reasonable, a tiny percentage might attack. I dont believe Ive been lucky all these months.
Most of the time it will be no different to solo