Great shoe for amphibious use. Seriously. I took these for a spin this morning while going out for a trip on my stand up board. I live by a lake with a rocky trail leading up to it, which is where I bring my board to launch it. The shoe was great for the hiking portion, super grippy, protective, etc. Once in the water, it gripped and protected from the rocky beds. I kept them on my feet while on my board, and it made me super comfortable that I wouldn't slip. Water drains right through the tiny holes in the sole of the shoe. I usually wear a 46 in other FiveFingers, and these were a great fit in the 46, so I'd say the sizing is consistent.