Speaking of le douche Campbell, I loved the little exchange between him and Don towards the end of Season 4 (could have been the next to last episode).
After Pete finds out that Don put up his $50,000 share, Pete is overwhelmed. He walks out of the conference room and catches Don's eye. He raises his glass to him and Don kind of give an acknowledging look/nod.
Powerful stuff man! They didn't even have to say a word and you know it was like "I got your back, bro".
Of course, there is probably some underlining motivation from Don there because Campbell is getting tired of his Dick Whitman shit, but there is still some genuine respect from Don towards Pete too.