One down, one to go...
It is best not to be watching TV while transforming Unicron, as it makes it take a lot longer than it should.
(I had the 1986 Movie playing, and thought I would have both transformed before it ends, but only had one done... because of the distractions.)
Those shoulder joints (at least on mine) are REALLY tight, and the connecting purple hinge pieces are not going to be load-bearing enough to transform this toy too often, as it is really difficult to hold the purple part tightly enough to stop the joint from taking any of the pressure from moving the arm (in the step before plugging it into the shoulder).
I'm not too sure about what to do with the screw covers. I don't want them to fall out over time and get lost, but I don't know if I want to risk gluing them in, in case, for some strange reason, I need to disassemble something and I can't then get to the screws.
So far, at least the good news is, neither of mine was missing anything, and the first one I have transformed didn't appear to have any noticeable defects preventing it from being transformed.