Enjoy your phenomenal Principia.
Dutch, so the brothers are a couple of 100 km from me away.
I cannot afford a Groenefeld, but superb that watch aficionados with enough money know where they can find Groenefeld.
I own a Frederique Constant watch to have at least a semi Dutch watch, but i like my American Bulova more!
I have a hate and love relation with my Frederique Constant, and a full strike honeymoon with an old cheap Roamer.
The dial, and that is similar in both cases.
Enjoy that special Groenefeld.