Sylvia is not world class at all!!!! Period bottom line......Arlovski is Skilled as a mofo no doubt but like most UFC fighters they are like big fish swimming in a small pond..Hands down the most skilled heavyweight MMA fighter in the game right now is Fedor Emealinko(bad spelling) Pride fightings heavyweight he would dominate either of those guys...Take it from me being in the mma game that guy has it all