I very much doubt there would be any humorous conversation between them at all, because if Angel ran into the Buffybot, he would be able to tell instantly that it isn't Buffy. Seriously. He's a vampire, a detective, and Buffy is the love of his life. Something like this is not going to get past him. The BuffyBot wouldn't smell human, let alone like Buffy specifically, because there's no possible way that Warren, with his human sense of smell and the equipment in his basement, would be able to manufacture the scent of someone he's only met *once* accurately enough that a vampire who knows the person in question very well wouldn't be able to smell the difference between the robot and the real thing in a second. The closest Warren could get to making the Bot smell like Buffy would be incorporating the scent of whatever shampoo she uses, but I don't think that would cover up the plastic smell, and it definitely wouldn't make up for the lack of Buffy's natural body smell. Also, to a vampire's sensitive ears, she wouldn't sound human, she would sound like a robot, because gears and circuits do not sound like a heartbeat. And she doesn't actually act enough like the real Buffy (or a human being at all, for that matter) to fool anyone who's really paying attention, and Angel's always paying attention when it's Buffy. Not to mention she doesn't have his bite scar (since I'm sure Spike wouldn't want that to be included on his toy).
Once he knows she isn't real, it wouldn't be hard to figure out why a robot version of Buffy was made, because a) she'd smell far more like Spike than Buffy and b) she'd be alternating between insulting Angel's hair in British slang and dreamily gushing about Spike. So, the only thing I can see happening as a result of this encounter would be an extremely ticked off Angel finding Spike and beating the unliving crap out of him for demeaning and objectifying Buffy in such a disgusting way. And then, if Spike were stupid enough to be snarky and defiant about it, Angel might just go all the way and stake him, because he wouldn't have the same irrational problem with the idea of killing Spike while he has the chip that the Scoobies have.
Now, if Spike had commissioned Warren to make him a Buffy *clone*, it would be a different story, but I still think Angel would be able to tell the difference from the behavior and lack of bite scar, it just might take him a few seconds longer to figure it out. And once he'd finished beating the crap out of Spike, he'd try to do something to help the Buffy clone, because clones are people too.
