I agree with everyone. There are several C/W moments that can be mentioned, the B/A spoofing being #1. Another favorite moment of mine was in YW when they were researching the tattoos:
Cordelia: Remember how I said, "Let's not have your department looking for those symbols I saw in my vision. Let's do this like we used to, you and me cracking the books"?
Wesley: Yes.
Cordelia: Well, that was dumb. What'd you ever listen to me for?
Wesley: I don't know. I think I sort of missed this. You and me and the books, ‘kicking it old school’, as they say. And I never will again
.
I love both of their lines. Wesley saying "kicking it old-school" is classic.