Back in January 2021, MB&F released what remains one of my all time favorite watches in the ?This is Totally Insane? genre of watchmaking. Regular readers will understand that this is actually one of my favorite genres – one that I wish more in our little world would aspire to, because, really, how many black dialed dive watches does one really need" The HM9 SV, short for Sapphire Vision, is, as described, a vision in sapphire. The design of this watch takes the already bonkers HM9 and essentially cases it in an elaborate array of sapphire crystals, with a metal frame holding it all together. The result is an incredible view of the HM9?s movement, which has two independent balance wheels joined by a central differential that averages out their rates for, in theory, more stable timekeeping. And it?s all arranged in a shape inspired by automotive design dating to the 1940s and 1950s, because this is MB&F, and that?s what they do. 
Last week, MB&F announced new versions of the HM9 SV, which is noteworthy because component for component, this has to be one of the toughest watches to make in the entire industry. The reason, of course, is because of the extensive use of sapphire, which has to be custom made specifically for these watches to very precise tolerances. And every piece of sapphire used in the HM9 SV is curved. MB&F points out that sapphire cased watches made by some of their competitors are using mostly flat pieces of crystal, hel...