I don't have that style of
Crocs, but I could never wear the ones I have all day at WDW. Though comfy, there's not firmness tothe support - so ultimately there's nothing to keep you form turing your foot in an odd way. I've also seen plenty of kids trip in them; the foam sometimes gets caught on hte pavement.
I also couldn't wear flip flops all day. Again, no side support is just one problem.
Good shoes are the most important investment for WDW. If you can't walk, your trip is over.
I did like the Tevas I have, they have the ankle strap. But even better than the Tevas are a pair of Ecco sandals I got on clearance for about $40. Perviously, I enjoyed Clarks, as one of my favorites. I sought the Eccos, because Clarks didn't make the style I liked last year...but this year they have brought it back in an improved version. Mine were like the Sunbeat or UnHull styles:
http://clarks.zappos.com/n/es/color/2/d/722001125/width/M_12/page/1.html
These kind of sandals offer a great combo of cushion and support, airyness and protection. So many times when I wore Birkenstocks I ended up getting my toes stubbed somehow.
The Longmeadow style also looks kind of nice, but sometimes with stat style of strap my pinky toe hangs out, which is really uncomfortable.
With the Sunbeat style the straps are wide enough to cover my toes. If you get blakc, though they are not glamorous, I feel they are a nice alternative for to sneakers for TS meals.
(The Eccos I have are like the Charm or 'Wave three' sandals:
http://www.eccousa.com/shoes/womens/sandals/68/product-list.aspx )