I love these slippers and Acorn is definitely on my radar when it comes to slip on and house slippers. I'm a size ten and a half and they fit like a glove, but I think they would be snug on a size eleven and a half. They are very comfortable and are suitable both for relaxing in the house and for leaving the house for a few hours. I wouldn't wear them unless I had a full 8 hour day with lots of trips planned. But they will probably be able to be worn all day, they might not be the best choice for that. There is a lot of support when walking and they have a thicker sole than many slippers. They just don't quite compare to a pair of Vans loafers in terms of outsole thickness. But they are equal in overall quality, which makes them worth their price even if it's a little high for a pair of shoes designed for indoor use.