Used these for a week on a recent vacation.  Spent time walking over sandy beaches, a bit of surf, slightly rocky areas, and gravel walks at the resort.  All were fine.  I tried not to get the shoes *too* wet, as they get heavy.  They are meant to handle the water, but that doesn't mean they won't get a little bogged down and soaked.  The sole appears to be a one-piece construction, and the insole is firmly attached.  No problems so far with peeling sole materials or the insole coming up and out of the shoe while walking.

I wear a size 12 and ordered the same.  I have a slightly narrow foot, and these shoes were "grippy" without being too tight.  They seem to fit true to size for me.  Time will tell if I have any quality issues as others have described, but after one week of regular daily use on the beach and paths, so far so good.