Why i dislike him? Well i was a fan until Hungary last year, and then i finally saw what he's like.
And i always had some drivers i "hated" on the grid... most recent ones would be Hamilton, Alonso & Montoya (there were a lot others in the past)... so he's just the last in line
The problem with him is that he's too arrogant considering what he has achieved in F1. I even saw a video posted here of him, when the camera turns away he turns to Kimi and says "I'm taking you down". He is really 2 faced. One for the cameras is all smiles and patting each other on the back and when no one is recording he's himself again.
He also doesn't drive aggressive, he drives dirty. He will literally do anything to score as much as he can, and still think he was right the whole way.
And his best characteristic is that he actually thinks he's better than the F1 greats like Senna or Schumacher...
My only hope is that next year or after that the McLaren sucks so much he has to fight for P14 or lower, and then he will see what's it like to have a car that's can't even score points. Then we'll see if he is so good like he thinks he is.
You can't be a F1 driver if your first 2 F1 drives are in the best car on the grid. If he started in a Minardi or Force India, and driven there for a year i would have some respect for him. This way i do not have any.