I'm a nurse and on my feet all day. I buy a new pair of New Balance 336 shoes every 2-3 months. When I go to WDW I take my prior two pairs of 336 shoes, as they are broken in and still look good. I also take a pair of water shoes for the water parks and a pair of black leather shoes that are well broken in for dressier nights. No blisters, ever. Bottom line for me is that I don't ever try new shoes on a WDW trip. Ever.