PvP MMO, obviously its that hard to make a good PvP mmo, unless you have all the same classes or ridiciulously simplistic classes then proper balance is nearly impossible.
But there are plenty of great PvP games.
Counterstrike
Battlefield 3
Starcraft 2
iRacing
Rfactor
Gran Turismo 5
Just a few out of many, main factor is that they are not MMORPG games. In my eyes racing simulations are one of the highest forms of real competitive skill based pvp.