I can answer what I think about your second point.
I think it is quite portable. Though it doesn't stop me from being extra careful if I ever lift it. I would of course secure every part inside to the max, if I want to move around with it often. I find the chassis to be very compact. Rather, it keeps the parts and everything in, compact in a very "pressed" way. This said, when the computer was built with the Cerberus. I felt it was way heavier. Yet it wan't, because the compactness made the "newtonian force" fall more stable. Quite common with compact things. It is like comparing an UltraBook with a laptop having the same weight. Well, when thought of the compactness.
You could also get a stand for the graphics card. As somehow prevent some of the force of its weight pushing downwards, when moving the computer. Or custom make a stand. People do this sometimes. Sometimes a much heavier graphics card comes with a fan. And of course, most graphics card companies recommend to remove the graphics card when moving the computer. Assuming that would be a hassle for most people moving the computer much often than most others.
