I have the blue dial and contrast is still not great. Because of the polished numerals and hands, they often look "black" without direct light. And "black" on navy is also pretty hard to see. Its doable, but not at a glance in a lot of lighting conditions.
Longines does assembly, finishing, and their own modifications to the movements in the Longines manufacture. Teddy has also visited there and made a video on that. He was really impressed by Longines history and how much movement work they actually do "in house".
I think the framed date would look out of place here. Their other models with framed dates have applied indices, these are painted. The date frame would be the only applied thing on the entire dial.
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