I've had a big Cintiq before - an old 21" square thing, which would be too low-resolution for practical work now. But I miss that giant screen SO much... It's just lovely to be able to work zoomed out, yet still be able to see everything on the page in detail.
Apparently it's much better ergonomically as well, as you tend to use your whole arm to draw, rather than your wrist. Since the arm has less tiny bones and tendon sheaths and all that fun, finicky stuff you find in the wrist, you decrease the risk of RSI.
I use an iPad now too, and I am totally unwilling to give up Procreate, so I'll be on a small screen for the foreseeable future. I'm really tempted to get one of those mounts you have, so my arm can rest on it while drawing, but shipping that to Australia costs a LOT, haha. 