Omega Stories: The Omega Aqua Terra / Railmaster XXL Family

These watches are huge and some will write them off on that basis but the near 50 mm case actually wears better than many will expect, and definitely better than some of the larger chronograph models.

At the time the XXL line was launched in 2003, Panerai was really starting to hit its stride, and IWC had just released the Big Pilot a year earlier. This style of oversized, pocket-watch powered watch were instantly popular and selling well, but Omega had never really been deeply into that type of watch. [..]

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The 6497/ 6498 movement that you discussed was also used in the Aero 45 produced by Archer watches. The movement has COSC like performance thanks to careful poising by the watchmaker.

And as you said, the larger watches that hold these movements are very comfortable. Nothing to shy away from for people accustomed to 39 to 42mm.