When he came home he was dancing and his back wasnt bothered. £90 instead of £200-300. Cancels out a lot of outside noise, but still loud enough volume to play my white noise at night. I wear a size 10 shoe, and the size 10 ONCAI flip flop was very acceptable in its fit,though my heel is right at the edge of the back of the flip-flop. Excellent overall. Update: It tore in a year and half. I tied it to the front and back roof racks (my side rack is only raised) and held very well for over 600km on the highway. I havent had a sandal like this before, so I cant compare to other styles. I started wearing them because I have problem feet, and I needed a house shoe with support, and when we put hardwood floors in our house because I couldnt stand the loud hard sole shoes inside the house. This is my second pair, same seller, same make.