Ciao Bruno,
thanks for remembering that Minerva calibers were used in other Panerai models too....I honestly didn't remeber that.
Concerning the choice of using Minerva calibers i think it is a huge step forward instead than using Unitas ones (even if well reworked by Panerai).
Nowadays Minerva is among the most acclaimed manufactures and the job did with Montblanc is a proof of that. Of course, it would be necessary to know exactly
which caliber is used here.
However it is Panerai heritage to make use of many different outsourced calibers (Rolex, Angelus etc).
Limited editions leave always me a little bit cold. Luxury watches should be limited by definition.....
Just my two cents,
ciao from Milano,
slide68