These things rock, just got my first pair today. Excellent construction and quality, and great leather footbed. The arch support is nice as well. It's also good to know that the purchase of one pair of Freewaters allows Project Freewaters to provide clean drinking water for one individual for one entire year.
The only con I can think of is sizing - these tend to run just a little bit more narrow. I suggest going up in size, probably no more than one full size, to compensate for this.
These things are pretty comfortable. They seem to have decent support and you won't mind wearing them for decent walks. I got them mostly for beachwear, and they hold up to the task. Some have gel soles, and I would put down a little more for those if you want the ultimate, but for a nice-looking pear of comfortable flip flops these guys get the job done.
I do also suggest going up an extra half-size or so if you want a wider fit.