Nice question Bruno.
It is always difficult to make a balanced opinion considering we are so much influenced by owner's point of view we've been reading.
I prefer the 39.4mm over 42mm width but the style of the 5070 case+bezel+lugs is much more interesting to me than the 5170's (that's alwso why I love the 5975's case so much).
The 5170's case is quite simple and perfectly neutral in design (more classic). Hence, less enthusiasm.
However, the new movement (apart from the fact it is "in house" or not) is getting on board several new improvements, while keeping the aesthetical caracteristics of the Nouvelle Lemania.
The only little "cons" of the new movement could be one or two "angles rentrants" missing.
Personnaly, I would go for a 5170G is I had the money and were to buy a gold case chrono.
If I was to have the budget for the 5070P, I would have to wait for the 5170P, to see which dial is more appealing to me.
Are you tempted?
Cheers, Mark
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