I bought these as my sister and mother convinced me they would be the comfiest shoe I would wear all summer. They were right. Great support for my arches and with the slightly raised heel my posture is better. Very comfy sole, feels like your walking on air. I prefer to have the back strap as I tend to walk out of flip flops. As for size, I tend to take between a 7.5-8 in shoe size. I take a 7 in these.