I really like these slippers but struggle a bit with the flat footbed.  I wear them a lot and will wake up the next morning with stiff calves, feet due to them (I know because I didn't have that happen with my previous slippers.).  Next Ugg slippers I get will have backs as well as I think that will address the issue.  I love the Ugg brand but couldn't give these a 5 star due to the stiffness my legs feel.