>>724607623
Given that most modern games use the left thumbstick and face buttons as their primery input method then top is the best configuration as that is the place where the thunbs rest naturally, reducing strain.
Middle is good for 2D and indie games that still rely on the face buttons but control better with a D-pad than a thumbstick, otherwise it is just snoy retardation that forces the left thumb into an unnatural, strenous position for prolonged periods of time.
Bottom has the same issue as middle but for the right thumb instead, and really none of the advantages other than visual symmetry.