Also, all my watches are currently performing to chronometer standard, however some of them have been pleasant surprises…of course the Rolexes have flawless accuracy as expected so I included them. By far my most accurate watch is my GS with its new spring drive movement which has zero deviation as long as it’s running! Then there are the surprised ones! I have 3 in that category: my VC traditionelle has a 1 sec/day deviation and my up/down has a 1-2 sec/day deviation which were both an unexpected surprise for me. Also, my Longines tuxedo has 2-3 sec/day which is another surprise. Finally there are also the one you would expected, two master chronometers! Cheers