Got my Cuboid in the vape mail today! Cracked open the box and I'm impressed. Very small device. Folks are right, though, it's weighty. Moving to the Cuboid from an XCube II that I've had nowhere near the problems with as other folks have, here's my thoughts on the Cuboid...
The Cuboid is solidly built. There's nothing about this thing to me, that feels delicate. Was aware of the update, so I put the batteries in and went over the instructions, then went straight to 3.10. I exclusively use 316L SS wire, TC only for me these days. Using 0088 in the TCR mode puts me dead on and gives me a quick ramp up to proper temp with a steady hold until I let go of the fire button, compared to the XCube that had a tendency to pulse with coils that had seen about half their life. The resistance monitor in the Cuboid is also more accurate and sensitive. It tracked the changes in resistance as my coils aged, where the XCube II does not.
I was happy with my XCube II, so nothing here should be taken as a knock against Smok. The Cuboid is just a newer, better device that has improved upon what's already out there. I'm very happy with my purchase. I'm also starting to feel lucky in that I don't seem to be having the same problems that a lot of folks out there do with the new mods, especially when it comes to TC with SS wire. I love it, and rarely seem to have serious issues with it.