the Reverso TT1931 US Edition is a my go-to piece. The lack of logo and the subtle changes to the font and hands in this special edition means you really have to be in the know. But for those who are, it is always a conversation starter and I have had multiple WIS strike up conversations when wearing it in the wild. Above all, however, it's simply a great watch and design.
On a side note, I recently took my vintage Cartier Tonneau in for service at the local Cartier store. Upon return the manager informed me that she had shown the watch to all of the staff, who had been admiring it and comparing to the new model. She even offered me the service free of charge. For me that kind of recognition was particularly meaningful as it speaks to a brand (and its employees) who value their past just as much as their present. My respect for Cartier grew immensely that day.
Featured before in WristScan but here is a fresh picture: