I have the blue dial CSO and I wear a suit every day to work. While I don't wear the CSO every day I would say that the blue dial matches every shirt/tie/suit combo that I own. The black would also, but I think the blue is a much nicer look IMHO. Def try it on first and see how you like the fit, I love it, I also have a Chronomat and I think they both fit equally as comfortably.
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Breitling Navitimer 01 46mm
Breitling Chrono Avenger

Breitling Chronomat Evolution
Breitling Chrono SuperOcean
Breitling Avenger Seawolf
Omega Seamaster Pro James Bond LE Co-Axial Auto