He was boring in 1.
He pissed me off in 2.
He saved my life in 3 and I made sure to visit him in the hospital as often as possible. My Shepard wasn't nice, but she wasn't an unnecessary bitch, either.

He also has one of the best scenes in the game, inquiring about your time with Cerberus and your views of The Illusive Man. It was the one time in ME2 the game actually let me roleplay my Shepard like how I played her in 2.