Comment by yobbo

I have a 7s26A movement out of a late 90s SKX which was unserviceable, and another 7s26C became unusable after 4-5 months of use.

I also have a replacement 7s26C which worked flawlessly [-5,+5] s/d out of the box and a year so far, and another watch with NH35 which still holds [-5,+5] s/d after seven years of daily use.

There are stories of SKX:s which hold good time after 20 years.

There are much cheaper watches than SKX (at their current prices) that will withstand the depth, see "Beyond on the press" pressure chamber tests, for example https://www.youtube.com/watch?v=Ti-GdfGbj4Y