Maybe I should add that this turret is only 3.08 mm high.

I pride in pushing MoI (and Flamingo for rendering) to the maximum, but it is unlikely that a very slight curvature glitch could be rendered in the real world even with current leading edge 3d printing equipment. Even for a screen rendering of a completed aircraft, the bump maps alone would probably cover the glitch, even in a close up view.

Nonetheless, this shows that utmost care is required if going for top smoothness, but the tool can do it. I love MoI !