I started out by purchasing the wrong size and Amazon made returns very simple.  Please, if you've never worn the Crocs, find a Crocs size chart, print it, and find your size.  Their sizes are different!

The shoes themselves are cool and comfortable, lightweight, and are easy to kick off/slip on quickly.  I wear mine when I go on my daily walk.  They probably aren't the best ergonomical walking shoe, but I find them comfortable and that's what matters most to me.  I wear mine to work and at first I felt like I was really doing something daring, but soon realized that no-one really noticed.