Sunnydale was a town full of vampires and Buffy kicked all sorts of ass and took all sorts of names.
Barrow was a town full of vampires. Vampires who were apparently thwarted by boiler rooms (since that's where the townspeople hid out more or less successfully for most of the story). Therefore, Buffy will also kick all sorts of ass and take all sorts of names.
Furthermore, Buffy now has an army of slayers at her disposal, and the ability to call in reinforcements from the "Angel" crew.
There is really no question here. Buffy wins.
