So after months (years?) of searching for my ideal watch I decided on a 5164. And I love it. 
However, a couple of days I was surprised in the dark....
An email and then a visit to my excellent and most helpful AD confirmed that the lume on the '1' of the 10 was missing! He quickly contacted Patek who confirmed they had a replacement dial waiting, and so off it went...and was back on my wrist 10 days later! Fantastic service I think - from my AD and from Patek. Out of interest, would anyone have kept the 'unique' dial?