I recently purchased a Gopro hero 4 silver, and tested it out down in Coolangatta and Tallebudgera Creek. I also have the KNEKT setup with the trigger and 6inch dome for underwater shots.
I know there is a lot of negative talk about people using Gopros to get photos but having had a water housing in the past I wanted something I could use in the water for my photography but also use with my kids when I am at the beach without stressing about my camera the whole time. Plus who cares what people use as long as they enjoy what they are doing.
The GoPro with the Kneckt trigger is really easy and comfortable to use and is fun to use. I am still getting the hang of it and look forward to getting more shots in the future.