Comfy. No need to break in. I wear an 8.5 and 9 fits great. Had my last pair for 5 years then finally ordered a new pair. Still have the old ones for when I paint or do other odd jobs and don't want to get the new ones dirty. Foam gives some support yet molds to your feet. I use them mainly around the house, like summer slippers. I don't think I would try to walk around the zoo all day in them or anything. they just don't have the support and I'm just about flat footed. I would definitely recommend them!