OK, so about Pamela...
I have not started watching season 5 yet, but the last few episodes of season 4 with Pamela were at times a little painful.
Seriously - is she supposed to have some sort of personality disorder or mental issues? She goes back and forth between being a pretty cool chick to a pretty crappy person fairly regularly and with little warning, and for me the good stuff is not nearly good enough to have to put up with the bad.
(Having said that, I've never slept with her, so maybe Louie's got more of a vested interest in sticking it out.)