I just received this today. I have the FISH theme. The fit was good. I wear a size 9 and ordered US women 9/10. There's a little more space; not too tight so I would say they are true to size. Haven't worn them in the pool yet so I'll have to report later on how they hold up/behave over time. The insole lengthens, so it can be removed if necessary. Update: after a few months the shoe has held up well and is still very comfortable.