Hi there, just wanted to share my experience with my 2yo AT, it was fast around 4 secs/day since the beginning, so i took to AD for a regulation/calibration(before the guarantee was over), and it has been since then around +0,5sec/day constant, i did try different positions overnight and it can also loose a bit when on crown - so thats very nice. I have the same experience with my speedy pro (1863), i got it regulated and now it looses 1sec over night when on crown, and gains 1 sec when worned, so im very satisfied...

p.s.
And my Seamaster 300 Quartz is always on time

Have a nice day all