This is a subject matter that I wrote up sometime ago. Thought it would be an interesting departure to talk about a Patek "simple calatrava".
The 5296 design can be traced to the famous 1930's ref.96 (sector dial), right down to the same style blued hands. The case of the original ref.96SC (of which the Patek museum has one example) is approx. 31-32mm vs. 38mm for the 5296. In addition, the 5296 now comes with the extra small complication of the date aperture. Although the date feature is quite practical, my preference would have been to omit this feature, as it would give the dial a cleaner look.
I've always been fascinated by movements (collected vintage Pateks with a movement theme, ie 27SC, 27-460,12-600at, 27-400AM etc). So, I decided to do a bit of research on the calibre 324.
Essentially the cal.324 is a direct descendant of the 315, with a higher beat count (28,800 pbm). In addition there are some additional technical improvements to the original base cal.315.
What I did find quite interesting is the cal.324 has an "indirect centre seconds". As most vintage Patek collectors are aware, early indirect center seconds movements are quite coveted by collectors.
According to Walt Odet's excellent article on this subject, he states the following (referring to vintage Patek movements):
"The indirect seconds was considered enough of a complication that an eminently capable movement maker like Patek often had the complication produced by an outside vendor"
He went on to say that "indirect center seconds are still used in more expensive movements like Jaeger LeCoultre caliber 889 and Patek caliber 315, and some Piguets. In less expensive movements, where the complexity and cost are prohibitive, indirect centre seconds is now rarely seen"
Here's a few pics of my 5296G (not the best quality, but the best I can do today):