So, I'm lttp on the DLC since I have been away from my console for a few months (and will be for another 6+ months a week from now). But I got it this week and have been playing it a fair bit (have beaten the first two bosses).
I tried the PvP arena today with my non-pvp focused SL 75 character (my only character). First, I tried a few duels. The first one was good. Managed to get a kill but was then killed with a few seconds to spare ending the match with a draw. Was a good opponent and a fun battle and we both bowed very courteously afterwards too. The rest of my attempts were against another guy who was really boring. He basically only went for backstabs and ran away when he got the lead. I got bored of that after a while.
I tried out deathmatch, instead. And that was really fun! With the more chaoitic nature of a 4 players free for all, only going for backstabs wouldn't quite cut it anymore so the battle was more fun and varied. And with the rules favouring surviving rather than killing, my defensive character was actually able to compete. I actually even won the match! The deathmatch was tons of time, but I don't know whether I will have the patience to wait for another game to start. It felt like I had to wait for half an hour, even though it probably was a lot less than that.