I ordered a 38mm and received it on Friday. I was initially a bit concerned about the size, thinking I might have gotten it wrong (mostly due to the smaller screen size and possibly battery, but also because of aesthetics), however as days went by I realized just how comfortable and somehow subtle it is when compared to other smartwatches I've seen around. It's not a gadget, it's more of a watch (sure, there are watches out there way bigger than 42mm, but you get the point...).
Today, I'm basically struggling to see the real value in getting the bigger version. I mean, is it bigger really better for something you have stuck to your wrist all day? Battery life differences aside (which are anyway not clear at this point), both watches are just perfectly usable and navigable, there is no problem whatsoever with the smaller screen. Checking notifications, sending messages, doing workouts, etc, are things that don't really require any additional real estate.
I have to say I'm not a big guy by any means, my wrists are about 55-60mm in width, and I have rather thin fingers too. I could see someone not feeling comfortable with the 38mm one, but I think a huge amount of people are getting the 42mm version just for the sake of getting the biggest one possible.
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