One thing I will add: specifically for the Speedy Pro, it is not COSC certified thus the tolerance is -1 to +11 seconds per day. As I, along with many, have learnt (notably from excellent posts by Archer here) there are indeed many factors that affect accuracy and indeed how the tolerances are applied (positional variation, temperature etc).
I've had my Speedy Pro for just over a year now (bought new) and it's hardly been off my wrist. I keep a track of the accuracy and found that as I have travelled round the world, different locations, climates etc have affected the accuracy in various ways. I not only know know this, I know how it runs when resting in various Positions. It runs slower when dial up, faster when crown up. I then use this knowledge to keep the time within 10s of atomic time, without ever actually adjusting the watch.
Some people may think this is a bit OTT and not required or a lot of hassle. However I need my watch to be reasonably accurate, and I have enjoyed the process of learning exactly how my watch runs and operates in different environments. It allows me to bond with the watch as mine and mine alone, not just another quartz or even another Speedy!
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