I totally thought he was gonna get his chip out. And I totally thought he'd manage to at least bite her. I thought he wanted her dead, dead, dead.
The problem with that, of course, is that he seemed to like her. I'm not talking about love or obsession here. We all know how he is. He liked things vamps aren't supposed to like: alcohol, bloomin' onions, chicken wings, hot chocolate, football players, Drusilla... hmm. I'm noticing a pattern here. He likes things he can eat. He's a vampire, so he could eat the Manchester United team if he wanted. Crap. See, I was gonna say he liked things and "people" and maybe he would have refrained from killing Buffy just for the sheer joy of continuing to fight her. But now that I listed all of the things he likes, I definitely think he would have bitten her and drained her.
So, yeah. I think he woulda killed her.