I tried them. But didn't feel they were worth the price.
In the summer I wear water shoes/river shoes whatever you want to call them, thin soles open weave cloth uppers, same as the 5 fingers without the toes....
they don't really seem to offer anything more than "hey, those are neat" comments.
When I say I wear them in the summer, I mean I wear them all summer, as soon as it hits about 45 degrees and snow starts melting I dig them out and that's what I wear.
The only time I don't have them on is when I have to 'dress up' or when I ride the motorcycle, then I keep them in the saddle bag and change when I get where I'm going.
Used to wear moccasins, but it got so getting good moccasin leather wasn't so easy any more, that coupled with time constraints, concrete, and the availability of water shoes lead to the switch. (but roughout conveyor belt material makes nice moccasin soles for urban use)