I tried those sandals on the other day (I love how they look) and they were really awkward and strange when I walked. The way the shoe moved or didn't move with the foot just looked really weird.
I have the sandals. I wanted some flat sandals I could dress up or down. I'm still getting used to walking in them. It's kind of strange to have nothing on the sides to keep your feet landing in the middle of the sandal. However, they're really comfortable and I didn't get any blisters walking in them for a full day and I got a ton of compliments on them.