Comparing to my 15202 rose gold, I can tell a few things immediately:
A) The 50th winding and setting mechanism is definitely smoother and more efficient, and the setting of the date is such a breeze
B) the 50th lugs are much more "flush" and "thin" to my wrist, providing a much better and more comfortable fit
C) the 50th Bleu Neut colour is a blue grey (a la the original) vs a brighter blue in the 15202, allowing for a more subdued and elegant look
All in all, an incredible piece and of course, getting the 50th model for the 50th anniversary is icing on the cake. I'm super happy and humbled to get this piece
Cheers
Peter