Hi all - I have a bit more experience with vintage Omega, but i've been bitten by the Heuer bug. I've always admired the Monaco 1133, but what are thoughts on the Monza 150.501? Specifically, is the caliber 12 or caliber 15 more "desirable"? I think the brass PVD is quirky and interesting. Would it be my only vintage watch? No. But as an F1 fan and Ferrari fan, I think the Monza is a fun entry into vintage Heuer.