We substituted Cocchi Americano Bianco for the Vermouth Bianco...slightly less sweet and slightly more bitter...better for us as a complement to the Mezcal and orange bitters.
This is seriously good tequila martini. Balanced and subtle and full of the range of flavors. The only thing that I modify at least at home is to pour more mezcal into the glass and then discard it into the bartender rather than the sink.