Hello!
Overall, the latest VSF V2 had a 12H GMT function.
There was a short period in which the first P.9001 used the 24H function similar to the previous 7750, but they were quickly replaced by 12H. because 438, 441, 320 the most popular models had 12H GMT. The same fate befell the PAM531.
These models on the p.9001 clone with 24h were not sold very much, and they are rare, and I hardly saw any mentions of PAM531, except in this thread.
In general, you should choose if you want the correct gen functions and balance wheel position but 12H and choose VSF V2, or take earlier V6F with 24H but not correct functions and balance wheel position.
Any of them, except for VSF V2 (and that should be clarified), will have to look for m2m.
Also, if you are considering a new watch, let me remind you that all questions are best addressed to your TD.
Good luck.