Not suitable for 57 inch. Horizontal bracket is too weak for the projection of the 57 inch. Always tilts down. Had to make special adjustment to keep it horizontal. The extension arms are strong enough.
I use this monitor arm for my Samsung Odyssey G9, works for me without any problems. The Neo G9 should be a little lighter than the G9, so the weight is not a problem. So the arm will hold the Neo G9 without any problems.