Good review and I will only add that I have an R1 and I have been able to compare it in the same conditions with the Sony A1 regarding AF and there is no comparison regarding eye and animal tracking. In the same conditions, the R1 continually lost focus on the eye with a leopard, with lions when they closed their eyes or turned around while the Sony A1 kept it without a doubt, with the eye closed, when it turned around it kept it where it was (turned) or with the leopard it did not hesitate between the eye and the black spots, when the R1 went to the head without detecting the eye. I think that Canon has a major problem understanding the subject, especially in animals (perhaps now somewhat less in birds) but such a distance between a recent camera like the R1 and the A1 that is already 4 years old does not seem logical. Not to mention the A1 II... If we go to situations with grass between the subject and the camera the same, continuous loss of AF due to the algorithm being unable to understand where the eye and face of the animal are. It\'s not a configuration issue, it\'s a matter of understanding what you have in front of you and Sony\'s, for the moment, are 1000 times better than Canon\'s AF (which is shared between its cameras regardless of whether some or others have better hardware like the cross-type AF of the R1).