These are lovely slippers. I am normally a 6.5-7, so ordered a 6.5 as recommended. Unfortunately they are still too big even with thick socks on.
I took note of other comments and, as I usually wear 5.5 shoes, thought the size 5 should be fine. But even with substantial socks they were huge. You don't necessarily want to go and find thick socks every time you put your slippers on - like first thing, when you get out of bed. So have sent them back (at my own expense) to get size 4. Hope they fit because I love the look of them.
The description of them clearly states: "These Slippers were designed to be worn with thick socks and are a bit over sized to allow this."
So this part of your review is irrelevant.
I got my partner a pair in her size and she has found no oversize problem with them.
Bought these slippers having seen them being advertised and have to say the delivery was quick .
The actual slipper itself is very nice , however the sizing is a little big I ordered a size 5 and could have had a smaller size, as the slip off my feet too easily , not good when going down the stairs like them though so would recommend