I am only pointing this out as nobody has mentioned the obvious, which is that you can resize the 2D panels. In other words you don't have to have the main panel distorted, you can just resize it to make the gauges round again. I don't use the 2D panels but if you don't want gaps at the sides you could fill them in with some of the other pop-up panels - radio, GPS, whatever, depending on the aircraft. Seems like a poor reason to limit the choice of monitor to me.