These were so comfortable out of the box when I first tried them on I actually forgot to take them off and wondered around the house for hours. Finally realized they were still on my feet when I sat on the couch and put my feet up and realized I didn't have my slippers on! Now after a couple weeks of working in these everyday on hard concrete floors they're even more amazing. No aching back at the end of the day. Highly recommend for spending the day standing, especially on hard floors which was exactly why I bought them.