Outstanding for flat feet. I overpronate quite a bit as well and these shoes are a dream to walk and even just stand in. Bought these after seeing a few sites recommend them for flat feet and they were absolutely right.Turns out it's a little more complicated than just massive arch support that you have to look for. Too much will just hurt the inner part of the foot if you're flat footed. These have moderate arch support and fix the issue in other ways like the heel cup, among other things I'm sure.I never realized how much of a difference the right shoe can make and I've never worn anything so comfortable. Takes a bit of getting used to at first since it completely changes how I walk and how my knees feel especially but I love them.As for long term durability, no idea yet. I've only walked/jogged a couple miles at a time for exercise or worn them normally throughout the day but they seem to be holding up just fine. Will definitely be getting these again down the line.