If this was directed to me, I need to start with some caveats. First, I've been through rsingler's course and service my family's regs but I wouldn't call myself a technician. Second, my direct Mares experience is limited to the previous generation of these regs, specifically the 22, 32, 42 and 15 first stages and Proton/Proton metal and Rover/Prestige seconds.
That said, I would happily dive with the 62X Dual Adj. The second stage had been around for a few years and I haven't seen any complaints. And, while the first stage is new, it appears to be essentially the same internally as all the Mares diaphragm regs starting with the 22. The difference is that the body has been trimmed down as much as possible to allow for a more compact and lightweight reg.