I take to surf for 8 days and the pool on my holidays. Almost 10 hrs at day underwater, ocean/pool and the iwatch work fine.

My concerned was the silicone band is this can hold and maintain the iwatch series 2, in his position.

The silicon band work perfect never feel that the iwatch can lost or feel loose.

you should used the screen protector due this iwatch screen has a special magnet to hit the screen. I note 2 nasty scratches on screen protector.

In general the iwatch accomplished that they promise, yes you can surf with the iwatch.

The bad:

lose the connection between the iPhone and the iwatch very often due a Bluetooth distances.

regards