The lack of an adjustable heel strap makes them very difficult/impossible if your feet are easily sweaty, which is not unexpected in warm weather. The upper elastic doesn't do much because even when completely loose, the sandal barely flexes.
Pros
It's been a few weeks and they're still like new. The durable outsole and the Velcro straps still hold up well. Fits well too.
Cons
Adjusting the straps for a comfortable fit is not easy