The Okabashis came back sooner than expected; they also sent the pair I wanted in exchange, which I was kind of surprised about (see this post about returning the defective pair). I decided to get another pair of the EuroSport sandals that I have worn daily for about two months with no problems whatsoever, and chose a pair in navy to fit DJ. He says he likes them because "they have the little bumps that massage your feet." So now we have matching sandals and he does not seem at all perturbed by this. I'll give it another year.