I tried these on in store the other day while I was working and can not get over how comfortable they were. The leather in the upper is super soft, and underfoot it was like walking on little clouds!! I am not normally a slides kinda gal, but after chatting with the team member in store who has five pairs of this exact style in different colours, I have added them to the very top of my wishlist! I am a 39 with a high instep, and I could go for either the 39 or 40, depending on how firm I want them to feel, but have the adjustability in the buckle, so will probably go for the 40 to allow for my feet to be a bit hotter while on my holidays this year.