Who is the better world class batsman -> AB de Villiars or Virat Kohli ?

In the form Virat Kohli and de Villiars are is incredible. In this ipl, Virat kohli is the player with most no. of runs i.e 919. With final is yet to happen, we all are hoping that he will cross thousand runs in a caleder year which is the most by a bats man and is a huge achievement to have as nobody in any season of ipl have made 1000 or more runs. 

Where as de Villiars is also maiking it big by contributing at crucial stages when required. As all of us know what are the achievements of de Villiars. He recently completed his 25 000 runs in all the format. What a amazing achievement it is. So it is a very big question of debate that who is the best among them. 

So, we ask this question from you guys. Kindly give the answer with proper reason in support of your answer. 

                                  # Comment your answers with the proper reason !!!