Oh, James can be chatty. But that's mostly the Doctor part of him, really, and thus not really applicable in this situation. The Master doesn't chat just for the sake of it, unless it's someone in particular - which mostly means the Doctor, honestly.

"In the subway?" he asks, crossing the street when the light changes. Interesting place to have a base... Unless she means they actually have to take the subway somewhere. In which case he's going to have a problem, having no local money on him.