I am on my feet all day at work and have tried all kinds of athletic shoes trying to find something that stays comfortable for 8 hours. The 559's from New Balance are the best I have found.
I wear them 5 days a week all day and have to do a lot of standing and walking. My last pair lasted me 8 months before the cushioning finally started to give out and I had to replace them. Think of how long they would last if you just wore to walk an hour or two a day! Highly recommend.