It probably is already discussed on this site ...
But here is an official email I got from Patek telling why the first aquanauts got the cal. 315 while others got the 324.
Dear Sir,
We thank you for your mail we received via our Website.
Kindly note hereafter our reply to your questions :
1. New Caliber 324
Kindly note that our Caliber 315 SC will progressively be replaced by the Caliber 324 SC AIG.S - an improved movement, and this is forseen as of April 2008.
It is possible that some 324 Calibers has already been mounted in some models.
For the end user there is no difference in terms of accuracy and reliability between the Calibre 315 and the Cal. 324. The advantage of the Calibre 324 vs. the Cal. 315 is a gain in efficiency and time in terms of our watchmakers’ work as it is easier to time the calibre 324 to the Patek Philippe high precision standards.
For your information, only the referende 5127 rwill emain equipped with the Caliber 315 for the time being. Patek Philippe does not divulgue the information about quantities of Aquanaut delivered with cal. 315.
Sincerely yours,
NORTHERN EUROPE
Patek Philippe S.A.
Chemin du Pont-du-Centenaire 141
CH - 1228 Plan-les-Ouates
tél. +41 22 884 20 20
fax +41 22 884 20 40
So it seems that only the first 2-3 months they got the 315, afterwards they started using the cal. 324
So, is it important ? i don't know but you can say the 5167 with 315 cal. is very rare.
Patek makes about 700 mechanical Aquanauts per year. Which is more or less 60 per month.
So, in the 10 next years to come, Patek will make about 7000 Aquanauts but only more or less 150 (?) of them will excist with the cal 315.
