I have had a Rolex Submariner since 1981, VERY expensive o/h a couple of years ago, reliable in extreme heat / cold but not as accurate as you might think. Although -5 secs a day is not bad for a mechanical watch. I also own an Omega Speedmaster chrono, bought 1969 ( before moon landings) keeps reasonable time, last serviced 20+ years ago. Took it to dealer recently for a check, told "if it runs ok don`t open it". Had a few straps over the years. In my opinion THE classic chrono.