Wore while snorkelling in the Maldives. Nice tight fit and although can be a little tricky to get on in the water they certainly won't come off while swimming or snorkelling! Be careful not to get sharp sand/stones in them while putting on the water as to me cost it is quite painful. Overall though very helpful while snorkelling in both calm and stronger currents and helped me swim much better than not using fins.
Easy to get on and off. Fit well.
Protected my feet (to some extent) and helped me swim whilst snorkelling.