If you are thinking about the regular Superocean 42 or 44, they and the Aquaracer will both have either an ETA 2824 or Sellita 200. However, the Breitling will be within chronometer timing specs, the Tag will be +/- 2 minutes per week vs around +42/-28 seconds per week at the worst for a Chronometer. Both will come with a 2 year guarantee and have 38 hour power reserves. But the Tag will have a ceramic bezel and cyclops for better date legibility.
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