I can't speak for the server so I don't claim to.
With that said, I have had many rp encounters in the open world without being attacked. And those times when a rp'er was attacked, the player from the other side I was rp'ing with would explain to them that we are rp'ing, and usually I would still be alive and the attacker would apologize.
There are also a number of guilds that respect the rp side of the server as well, and won't intentionally inturrupt someone that is rp'ing.
What it all boils down is that yes you can have some decent rp here, but there is no promise you won't be attacked.
This is pretty much the gist of it. The PvP community here is pretty solid, but they usually don't stray into the Open world unless there is PvP to follow.
I've never been attacked while RPing. That may be pure luck, but at the same time, no one in my Guild has complained about it, so I have to say its not really a big issue. Most people here rolled on Jung Ma for a few reasons, such as they legitimately like RPvP, or perhaps they just wanted a PvP server without the immaturity other servers can have. Generally, people associate RPers with mature, respectful people.
The RP community here is very strong and active. If you simply look for it, you'll find it!