I don't know how many different lines there are, but they're there, and it's certainly not capped for only happening at max friendship. Raymond likes, I think, chai tea or something, and Marshal likes something else, to the point he said Raymond's house smells too much like whatever it was he liked and it made him wonder how he could live like that, LMAO. Raymond, who was my first smug, on the other hand -- though I've talked to him at least once nearly every day, hasn't said anything even similar about Marshal's house, even though I'm sure he's still programmed to have a line @ another smug like Marshal.
So, either way, I've found them different enough, insofar as the overall lazy dialogue of the game as a whole.