My experience with Sanuks is "different".  I tried 12s originally, but my 12.5 feet always touched the end.  I now have a 13 which fits a lot better, but I had to modify it.  What I have now is a model in crinkled leather that they've apparently discontinued.  (What else is new)?  I have never been able to wear a slip-on because of my narrow , non-volume feet.  So what I did was put in a backpacking insole from Spenco that has a wonderful arch support and a metatarsal "bump" just behind the ball of the foot.  These insoles are quite a bit thicker than standard ones and have a plastic underpinning that works for me.  They are just short of qualifying as an expensive orthotics.  I've used them for many years backpacking and I use them in all my other shoes.  Then, I gathered the top material to about 1/4 inch high and 5 inches from the upper end.  Then stitched it closed with nylon thread making the gather about 3.5 inches long between the upper end & the toe.  The "pinch" has no effect on the looks, IMHO.  Absolutely perfect fit for me!  The heel pops off once in a rare while, but only if I catch it on something.  This fix wasn't difficult at all.  Because of the modification, I'm looking forward to getting the Donny Primo and the one shown here.  Amazon still has the best prices on these, even when others are offering a 15% discount.  No tax & free shipping is a big bonus too.