I've worn more pairs of 574s than I can remember and most recently had to discard the now extinct 1320. Always had a size 12. They looked like a combination of both β firmer heel support and construction like the 574, but with a softer foam midsole like the 1320. Flat feet move a little inside the toe, even with the added orthotic. A deal breaker for me, however, is the sock-like construction. It tingles at the top front, at the entry point, feels like the top is tied very tight but the bottomβ¦