Kingler isn't as good in the OU environment because of its bad Special Defense and average Speed. Kingler truly shines in the lower tiers because of its massive Attack and Defense, letting it set up Swords Dance and/or Agility with ease.:
EVs: 48 HP/252 Atk/208 Spe
Item: Life Orb
Ability: Hyper Cutter
Kingler should use Swords Dance against defensive teams and Agility against offensive ones.