repair or defect only
I have heard of people here in Palo Alto and Stanford going in and getting REPLACEMENTS for defects, haptic didn't work, watch wouldn't charge, etc., and they DID have watches (they have just swapped out the aluminium or the SS head unit, swapping bands with the owner) but have NOT made inventory available for exchanges..
:-(
Ordering a 38mm and needing a 42mm or vice versa was QUITE common, especially for the ladies or men with girly wrists...;-)
Some people overcame the risk by simply ordering one of each (not really a great solution)
Personally, I think it was a bad idea for apple to not AT LEAST have mockups in the store. Even NON WORKING MODELS so people could try them on and see what would be best. Would have at least eliminate a lot of these issues.