I have mine since mid June 18, exactly two months, and about 6500 clicks on the counter. Eye-focus works when setting face priority. But before having the marketing name of EF, in most cases Face Priority put its focus already on the eyes even with the older models.
Eye focus with D6:
_D604310.jpgI made 3 car racing reportages, of which the two last ones in in Belgium, Spa-Francorchamps, during the last fortnight:
https://flic.kr/s/aHsmPSbgoGEuropean Endurance Championship
https://flic.kr/s/aHsmQ2bsnXWorld Endurance Championship
Both reportages are a mix of Nikon D6, for the action pictures, and D850 for the more still ones. As already mentioned, the D6 is an outstanding machine, well worth his single digit « 6 » attribute.
PS: I was one of the only 15 accredited photographers, and yes, no public.