Positive or negative spherical aberration- Which of the two provides better depth of focus by EDOF IOLs?

In the article in this blog 'Spherical Aberration, Q factor & choice of IOL' (https://www.quickguide.org/post/spherical-aberration-asphericity) I have provided an understanding on the subject of spherical aberration, the concept of positive and negative spherical aberration and how an IOL can be chosen for cataract patients based on the Q factor of the cornea. In this article, I will go a little deeper in understanding the 'best focus' or 'circle of least confusion' with spherical aberration and answer the following question:

Positive or negative spherical aberration, between the two what provides a better depth of focus?

To understand this we will first try to understand the concept of best focus with spherical aberration. In image 1, the axial or longitudinal spherical aberration is described as the distance between the paraxial focus and the marginal focus. We know spherical aberration provides depth of focus, but also degrades the image quality. This degradation of image quality is the result of the blur circle on the retina, as the marginal rays fall further away from the paraxial focal point. This is what typically happens in positive spherical aberration or negative spherical aberration.

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