I actually think the watch should be worn where the red band is on that guy's wrist. But otherwise that's how big the watch would look on my wrist.
I suspect if you show that photo to a dozen people, half will say it's the right size and others will say it's too big!
He looks much better in the 38mm. (modern buckle even)

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This is a very interesting thread. I am surprised that there are so many people with smaller wrists opting for the 42mm. IMO it will look oversized and toyish. I wonder if this will be a trendy way to wear the watch, similar to how people would wear oversized g-shocks.
Edit: Found a picture that shows the 42mm version on someone's wrist. This seems overly gadgety looking IMHO.
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This second image is a terrible example of anything and should not be used to draw any conclusions at all. This guy has either not finished putting the watch on or has never worn a watch and is clueless. That watch is not on properly, not even close. What we're seeing is the watch hanging off the wrist and thus can't be used for size comparisons or anything other than gawking at someone who is surprisingly unaware of how watches work