I go to bed at night having nightmares about this which, to me is the worst scenario. Never have felt really comfortable flying over long stretches of water but I have done it for years and no doubt will continue to do so.
Usual precautions - wear the jackets and have a servicable dinghy on the back seat. tied to the aircraft with a Swiss Army Knife in my pocket.
Sigh of relief when crossing the French coastline!!!
A2