Maybe he got the 600 in a server that was not X-Server yet? In my new server in 5.0 i went for 1500 points in the first month - which is not really hard to do, because if nobody is online you play versus their bots and you can just stomp it with like Edo Hiruzen while watching TV.

I would love to play more ranked arena, but ever since I hit 6th path, I wait for over 10 minutes just to find a battle. Not worth it.