I'm starting with 38mm stainless/Milanese; I've got smallish wrists (I'm a woman, yes) and I own a 38mm watch now that is perfectly sized to my eyes, so I was pleased to see that I would not need a larger watch if I bought an Apple Watch.
I have also ordered a black sport band that will look a bit more casual and I plan to try on the Modern Buckle in-store soon so I know which size to order once they're available.
But... one thing.
Because I often find myself "between" holes on watch bands, and because I often find myself removing watches once the buckle irritates my skin enough, I want an infinitely-adjustable band. But there will be times when the Milanese Loop doesn't fit well with what I wear -- I'm a jeans and t-shirt type who's far from a fashion maven. So it's a real shame that I can't get a Leather Loop with a 38mm watch.
I'm hoping that the sport band will be comfortable and will fit well in one of the sizes that come in the package. I'm glad it doesn't have a conventional (classic) buckle; it might do as a stand-in until someone makes the kind of band I want for the 38mm watch.
Alas, there's no way to submit product feedback for the watch yet so I can't find a way to ask for one to be made. (I do think that there should be a 42mm Modern Buckle, too, yes!)
If a third party makes a good-quality magnetic or Velcro casual band that would stand in for a 38mm Leather Loop, please let me know via PM!