But for my money, the guilloche dial is the way to go!
I'm not just saying that because it's the one I own. I think the painted numerals on the guilloche dial are far preferable to the applied numerals on the flat dials. I think of this watch as a ship's chronometer first, not a dress watch first, and the flat dial raised numeral look is more slick modern luxury than I want this watch to be.
Couple of photos to help persuade you